The Heidelberg Catechism: Lord's Day 40
105. Q. What does God require in the sixth commandment?
A. I am not to dishonor, hate, injure, or kill my neighbor by thoughts, words, or gestures, and much less by deeds, whether personally or through another; rather, I am to put away all desire of revenge. Moreover, I am not to harm or recklessly endanger myself. Therefore, also, the government bears the sword to prevent murder.
 Gen. 9:6; Lev. 19:17, 18; Matt. 5:21, 22; 26:52.  Prov. 25:21, 22; Matt. 18:35; Rom. 12:19; Eph. 4:26.  Matt. 4:7; 26:52; Rom. 13:11-14.  Gen. 9:6; Ex. 21:14; Rom. 13:4.
106. Q. But does this commandment speak only of killing?
A. By forbidding murder God teaches us that He hates the root of murder, such as envy, hatred, anger, and desire of revenge, and that He regards all these as murder.
 Prov. 14:30; Rom. 1:29; 12:19; Gal. 5:19-21; James 1:20; I John 2:9-11.  I John 3:15.
107. Q. Is it enough, then, that we do not kill our neighbor in any such way?
A. No. When God condemns envy, hatred, and anger, He commands us to love our neighbor as ourselves, to show patience, peace, gentleness, mercy, and friendliness toward him, to protect him from harm as much as we can, and to do good even to our enemies.
 Matt. 7:12; 22:39; Rom. 12:10.  Matt. 5:5; Luke 6:36; Rom. 12:10, 18; Gal. 6:1, 2; Eph. 4:2; Col. 3:12; I Pet. 3:8.  Ex. 23:4, 5; Matt. 5:44, 45; Rom. 12:20.
The Heidelberg Catechism: Lord's Day 39
Question 104: What is God's will for you in the fifth commandment?
Answer: That I honor, love, and be loyal to my father and mother and all those in authority over me; that I obey and submit to them, as is proper, when they correct and punish me;  and also that I be patient with their failings -  for through them God chooses to rule us. 
 Ex. 21:17; Prov. 1:8; 4:1; Rom. 13:1-2; Eph. 5:21-22; 6:1-9; Col. 3:18-4:1;  Prov. 20:20; 23:22; 1 Pet. 2:18;  Matt. 22:21; Rom. 13:1-8; Eph. 6:1-9; Col. 3:18-21
The Heidelberg Catechism: Lord's Day 38
103. Question: What does God require in the fourth commandment?
Answer: First, that the ministry of the gospel and the schools be maintained and that, especially on the day of rest, I diligently attend the church of God to hear God’s Word, to use the sacraments, to call publicly upon the LORD, and to give Christian offerings for the poor.Second, that all the days of my life I rest from my evil works, let the LORD work in me through His Holy Spirit, and so begin in this life the eternal sabbath.
 Deut. 6:4-9; 20-25; I Cor. 9:13, 14; II Tim. 2:2; 3:13-17; Tit. 1:5.  Deut. 12:5-12; Ps. 40:9, 10; 68:26; Acts 2:42-47; Heb. 10:23-25.  Rom. 10:14-17; I Cor. 14:26-33; I Tim. 4:13.  I Cor. 11:23, 24.  Col. 3:16; I Tim. 2:1.  Ps. 50:14; I Cor. 16:2; II Cor. 8 and 9.  Is. 66:23; Heb. 4:9-11.
The Heidelberg Catechism: Lord's Day 37
101. Question: But may we swear an oath by the Name of God in a godly
Answer: Yes, when the government demands it of its subjects, or when necessity requires it, in order to maintain and promote fidelity and truth, to God's glory and for our neighbor’s good. Such oath-taking is based on God's
Word and was therefore rightly used by saints in the Old and the New Testament.
 Deut. 6:13; 10:20; Jer. 4:1, 2; Heb. 6:16.  Gen. 21:24; 31:53; Josh. 9:15; I Sam. 24:22; I Kings 1:29, 30; Rom. 1:9; II Cor. 1:23.
102. Question: May we also swear by saints or other creatures?
Answer: No. A lawful oath is a calling upon God, who alone knows the heart, to bear witness to the truth, and to punish me if I swear falsely. No creature is worthy of such honour.
 Rom. 9:1; II Cor. 1:23.  Matt. 5:34-37; 23:16-22; James 5:12.
The Heidelberg Catechism: Lord's Day 36
99. Question: What is required in the third commandment?
Answer: We are not to blaspheme or to abuse the Name of God by cursing,
perjury, or unnecessary oaths, nor to share in such horrible sins by being
silent bystanders. In short, we must use the holy Name of God only with fear
and reverence, so that we may rightly confess Him, call upon Him, and praise Him in all our words and works.
 Lev. 24:10-17.  Lev. 19:12  Matt. 5:37; James 5:12.  Lev. 5:1; Prov. 29:24.  Ps. 99:1-5; Is. 45:23; Jer. 4:2.  Matt. 10:32, 33; Rom. 10:9, 10.  Ps. 50:14, 15; I Tim. 2:8.  Rom. 2:24; Col. 3:17; I Tim. 6:1.
100. Question: Is the blaspheming of God’s Name by swearing and cursing such a grievous sin that God is angry also with those who do not prevent and forbid it as much as they can?
Answer: Certainly, for no sin is greater or provokes God’s wrath more than the blaspheming of His Name. That is why He commanded it to be punished with death.
 Lev. 5:1.  Lev. 24:16.
The Heidelberg Catechism: Lord's Day 35
96. Question: What does God require in the second commandment?
Answer: We are not to make an image of God in any way, nor to worship Him in any other manner than He has commanded in His Word.
 Deut. 4:15-19; Is. 40:18-25; Acts 17:29; Rom. 1:23.  Lev. 10:1-7; Deut. 12:30; I Sam. 15:22, 23; Matt. 15:9; John 4:23, 24.
97. Question: May we then not make any image at all?
Answer: God cannot and may not be visibly portrayed in any way. Creatures may be portrayed, but God forbids us to make or have any images of them in order to worship them or to serve God through them.
 Ex. 34:13, 14, 17; Num. 33:52; II Kings 18:4, 5; Is. 40:25.
98. Question: But may images not be tolerated in the churches as “books for the laity”?
Answer: No, for we should not be wiser than God. He wants His people to be taught not by means of dumb images but by the living preaching of His Word.
 Jer. 10:8; Hab. 2:18-20.  Rom. 10:14, 15, 17; II Tim. 3:16, 17; II Pet. 1:19.
The Heidelberg Catechism: Lord's Day 34
92. Question: What is the law of the LORD?
Answer: God spoke all these words, saying: I am the LORD your God, who
brought you out of the land of Egypt, out of the house of bondage.
1. You shall have no other gods before Me.
2. You shall not make for yourself a graven image, or any likeness of anything that is in heaven above, or that is in the earth beneath, or that is in the water under the earth; you shall not bow down to them or serve them; for I
the LORD your God am a jealous God, visiting the iniquity of the fathers upon the children to the third and fourth generation of those who hate Me, but showing steadfast love to thousands of those who love Me and keep My
3. You shall not take the Name of the LORD your God in vain; for the LORD will not hold him guiltless who takes His Name in vain.
4. Remember the sabbath day, to keep it holy. Six days you shall labor, and do all your work; but the seventh day is a sabbath to the LORD your God; in it you shall not do any work, you, or your son, or your daughter, your manservant, or your maidservant, or your cattle, or the sojourner who is within your gates; for in six days the LORD made heaven and earth, the sea, and all that is in them, and rested the seventh day; therefore the LORD blessed the sabbath day and hallowed it.
5. Honour your father and your mother, that your days may be long in the land which the LORD your God gives you.
6. You shall not kill.
7. You shall not commit adultery.
8. You shall not steal.
9. You shall not bear false witness against your neighbor.
10. you shall not covet your neighbor’s house; you shall not covet your neighbor’s wife, or his manservant, or his maidservant, 10. or his ox, or his ass, or anything that is your neighbor’s.
 Ex. 20:1-17; Deut. 5:6-21.
93. Question: How are these commandments divided?
Answer: Into two parts. The first teaches us how to live in relation to God; the second, what duties we owe our neighbor.
 Matt. 22:37-40.
94. Question: What does the LORD require in the first commandment?
Answer: That for the sake of my very salvation I avoid and flee all idolatry, witchcraft, superstition, and prayer to saints or to other creatures. Further, that I rightly come to know the only true God. trust in Him alone, submit to Him with all humility and patience, expect all good from Him only, and love, fear, and honour Him with all my heart. In short, that I forsake all creatures rather than do the least thing against His will.
 I Cor. 6:9, 10; 10:5-14; I John 5:21.  Lev. 19:31; Deut. 18:9-12.  Matt. 4:10; Rev. 19:10; 22:8, 9.  John 17:3.  Jer. 17:5, 7.  I Pet. 5:5, 6.  Rom. 5:3, 4; I Cor. 10:10; Phil. 2:14; Col. 1:11; Heb. 10:36.  Ps. 104:27, 28; Is. 45:7; James 1:17.  Deut. 6:5; (Matt. 22:37).  Deut. 6:2; Ps. 111:10; Prov. 1:7; 9:10; Matt. 10:28; I Pet. 1:17.  Deut. 6:13; (Matt. 4:10); Deut. 10:20.  Matt. 5:29, 30; 10:37-39; Acts 5:29.
95. Question: What is idolatry?
Answer: Idolatry is having or inventing something in which to put our trust instead of, or in addition to, the only true God who has revealed Himself in His Word.
 I Chron. 16:26; Gal. 4:8, 9; Eph. 5:5; Phil. 3:19.
The Heidelberg Catechism: Lord's Day 33
88. Question: What is the true repentance or conversion of man?
Answer: It is the dying of the old nature and the coming to life of the new.
 Rom. 6:1-11; I Cor. 5:7; II Cor. 5:17; Eph. 4:22-24; Col. 3:5-10.
89. Question: What is the dying of the old nature?
Answer: It is to grieve with heartfelt sorrow that we have offended God by our sin, and more and more to hate it and flee from it.
 Ps. 51:3, 4, 17; Joel 2:12, 13; Rom. 8:12, 13; II Cor. 7:10.
90. Question: What is the coming to life of the new nature?
Answer: It is a heartfelt joy in God through Christ, and a love and delight to live according to the will of God in all good works.
 Ps. 51:8, 12; Is. 57:15; Rom. 5:1; 14:17.  Rom. 6:10, 11; Gal. 2:20.
91. Question: But what are good works?
Answer: Only those which are done out of true faith, in accordance with the law of God, and to His glory, and not those based on our own opinion or on precepts of men.
 Joh. 15:5; Rom. 14:23; Heb. 11:6.  Lev. 18:4; I Sam. 15:22; Eph. 2:10.  I Cor. 10:31.  Deut. 12:32; Is. 29:13; Ezek. 20:18, 19; Matt. 15:7-9.
The Heidelberg Catechism: Lord's Day 32
Question 86. Since then we are delivered from our misery, merely of grace, through Christ, without any merit of ours, why must we still do good works?
Answer: Because Christ, having redeemed and delivered us by his blood, also renews us by his Holy Spirit, after his own image; that so we may testify, by the whole of our conduct, our gratitude to God for his blessings, (a) and that he may be praised by us; (b) also, that every one may be assured in himself of his faith, (c) by the fruits thereof; and that, by our godly conversation others may be gained to Christ. (d)
(a) Rom.6:13 Neither yield ye your members as instruments of unrighteousness unto sin: but yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God. Rom.12:1 I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service. Rom.12:2 And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and
perfect, will of God. 1 Pet.2:5 Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ. 1 Pet.2:9 But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvelous light: 1 Pet.2:10 Which in time past were not a people, but are now the people
of God: which had not obtained mercy, but now have obtained mercy. 1 Cor.6:20 For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God’s. (b) Matt.5:16 Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven. 1 Pet.2:12 Having your conversation honest among the Gentiles: that, whereas they speak against you as evildoers, they may by your good works, which they shall behold, glorify God in the day of visitation. 1 Pet.1:6 Wherein ye greatly rejoice, though now for a season, if need be, ye are in heaviness through manifold temptations: 1 Pet.1:7 That the trial of your faith, being much more precious than of gold that perisheth, though it be tried with fire, might be found unto praise and honour and glory at the appearing of Jesus Christ: (c) 2 Pet.1:10 Wherefore the rather, brethren, give diligence to make your calling and election sure: for if ye do these things, ye shall never fall: Matt.7:17 Even so
every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit. Gal.5:6 For in Jesus Christ neither circumcision availeth any thing, nor uncircumcision; but faith which worketh by love. Gal.5:22 But the fruit of the Spirit is love, joy, peace, longsuffering, gentleness, goodness, faith, Gal.5:23 Meekness, temperance: against such there is no law. (d) 1 Pet.3:1 Likewise, ye wives, be in subjection to your own husbands; that, if any obey not the word, they also may without the word be won by the conversation of the wives; 1 Pet.3:2 While they behold your chaste conversation coupled with fear. Rom.14:19 Let us therefore follow after the things which make for peace, and things wherewith one may edify another.
Question 87. Cannot they then be saved, who, continuing in their wicked and ungrateful lives, are not converted to God?
Answer: By no means; for the holy scripture declares that no unchaste person, idolater, adulterer, thief, covetous man, drunkard, slanderer, robber, or any such like, shall inherit the kingdom of God. (a)
(a) 1 Cor.6:9 Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, 1 Cor.6:10 Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God. Eph.5:5 For this ye know, that no whoremonger, nor unclean person, nor covetous man, who is an idolater, hath any inheritance in the kingdom of Christ and of God. Eph.5:6 Let no man deceive you with vain words: for because of these things cometh the wrath of God upon the children of disobedience. 1 John 3:14 We know that we have passed from death unto life, because we love the brethren. He that loveth not his brother abideth in death.
The Heidelberg Catechism: Lord's Day 31
83. Question: What are the keys of the kingdom of heaven?
Answer: The preaching of the holy gospel and church discipline. By these two the kingdom of heaven is opened to believers and closed to unbelievers.
 Matt. 16:19; John 20:21-23.
84. Question: How is the kingdom of heaven opened and closed by the preaching of the gospel?
Answer: According to the command of Christ, the kingdom of heaven is opened when it is proclaimed and
publicly testified to each and every believer that God has really forgiven all their sins for the sake of Christ's merits, as often as they by true faith accept the promise of the gospel. The kingdom of heaven is closed when it is proclaimed and testified to all unbelievers and hypocrites that the wrath of God and eternal condemnation rest on them as long as they do not repent. According to this testimony of the gospel, God will judge both in this life and in the life to come.
 Matt. 16:19; John 3:31-36; 20:21-23.
85. Question: How is the kingdom of heaven closed and opened by church discipline?
Answer: According to the command of Christ, people who call themselves Christians but show themselves to be unchristian in doctrine or life are first repeatedly admonished in a brotherly manner. If they do not give up their errors or wickedness, they are reported to the church, that is, to the elders. If they do not heed also their admonitions, they are forbidden the use of the sacraments, and they are excluded by the elders from the Christian congregation, and by God Himself from the kingdom of Christ. They are again received as members of Christ and of the church when they promise and show real amendment.
 Matt. 18:15-20; I Cor. 5:3-5; 11-13; II Thess. 3:14, 15.  Luke 15:20-24; II Cor. 2:6-11.