In my Father’s house are many mansions; if it were not so, I would have told you. I go to prepare a place for you.
The “Father’s house”, of which the Lord Jesus Christ is speaking here, is the immediate presence of God in heaven. From there the Son of God had come to earth to become Man; and shortly before His death on the cross He explained to His disciples that He would return there after His resurrection. What was for them a completely new and tremendous promise was that He would one day take His disciples, i.e. all who have faith in Him, to be with Him there.
Owing to sin the human race had been banished from paradise and its nearness to God; so how could it now claim a right to such a heavenly blessing? Being pure and holy, God can have no fellowship with sin.
It was the Son of God Himself who opened up heaven for us. He did so in a twofold way. First, lost sinners had to be made fit for heaven. To this end the Lord went into death and underwent God’s punishment for sin. This benefits everyone who believes in Him and confesses the guilt of his life to Him. Through Jesus Christ’s work of atonement he has been cleansed of all sin and defilement and is free to stand before God without any fear.
Then the Son of God Himself prepared heaven for us by His return to glory. He had become a Man; yet He was God and Man in one Person, and has been ever since. Having accomplished His work on earth He ascended to heaven as a Man, the “Firstborn of every creature”, thus preparing “a place” for all who belong to Him. They will share His glory.