Sin separates us from God.

"But your iniquities have separated between you and your God, and your sins have hid his face from you, that he will not hear." - Isaiah 59:2 KJV

Yet, because our Heavenly Father loves us so much, He robed Himself in flesh and paid the price of His very own blood to reconcile us back to Himself. (Acts 20:28).

"And, having made peace through the blood of his cross, by him to reconcile all things unto himself; by him, I say, whether they be things in earth, or things in heaven.

“And you, that were sometime alienated and enemies in your mind by wicked works, yet now hath he reconciled In the body of his flesh through death, to present you holy and unblameable and unreproveable in his sight:

How?

“If ye continue in the faith grounded and settled, and be not moved away from the hope of the gospel, which ye have heard, and which was preached to every creature which is under heaven; whereof I Paul am made a minister;" - Colossians 1:20-23 KJV (1 Corinthians 15:1-4)

Peter preached the gospel on the Day of Pentecost.

“Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.

“For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call." - Acts 2:37-39 KJV