The Heidelberg Catechism: Lord's Day 18
46. Question: What do you confess when you say, He ascended into heaven?
Answer: That Christ, before the eyes of His disciples, was taken up from the earth into heaven, and that He is there for our benefit until He comes again to judge the living and the dead.
 Mark 16:19; Luke 24:50, 51; Acts 1:9-11.  Rom. 8:34; Heb. 4:14; 7:23-25; 9:24.  Matt. 24:30; Acts 1:11.
47. Question: Is Christ, then, not with us until the end of the world, as He has promised us?
Answer: Christ is true man and true God. With respect to His human nature He is no longer on earth, but with respect to His divinity, majesty, grace, and Spirit He is never absent from us.
 Matt. 28:20.  Matt. 26:11; John 16:28; 17:11; Acts 3:19-21; Heb. 8:4.  Matt. 28:18-20; John 14:16-19; 16:13.
48. Question: But are the two natures in Christ not separated from each other if His human nature is not present wherever His divinity is?
Answer: Not at all, for His divinity has no limits and is present everywhere. So it must follow that His divinity is indeed beyond the human nature which He has taken on and nevertheless is within this human nature and remains personally united with it.
 Jer. 23:23, 24; Acts 7:48, 49.  John 1:14; 3:13; Col. 2:9.
49. Question: How does Christ's ascension into heaven benefit us?
Answer: First, He is our Advocate in heaven before His Father. Second, we have our flesh in heaven as a sure pledge that He, our Head, will also take us, His members, up to Himself. Third, He sends us His Spirit as a counter-pledge, by whose power we seek the things that are above, where Christ is, seated at the right hand of God, and not the things that are on earth.
 Rom. 8:34; I John 2:1.  John 14:2; 17:24; Eph. 2:4-6.  John 14:16; Acts 2:33; II Cor. 1:21, 22; 5:5.  Col. 3:1-4.
Be on your guard; stand firm in the faith; be courageous; be strong. Do everything in love.