46 Then He said to them, Thus it is written, and thus it was necessary for the Christ to suffer and to rise from the dead the third day, 47 and that repentance and remission of sins should be preached in His name to all nations, beginning at Jerusalem. 48 And you are witnesses of these things. 49 Behold, I send the Promise of My Father upon you; but tarry in the city of Jerusalem until you are endued with power from on high.
I think that about sums it up. And did Jesus say "Grace", no He did not because His very Finished Work of His death and resurrection is the Grace Paul writes in detail about. The ACT of shedding Blood, His death and His resurrection speak loud words from the pages of the OT. These were words on the day of Pentecost the Jews there knew. They knew the Suffering Servant of Isaiah 53; they understood there is no forgiveness of sins without the shedding of blood. They knew the Psalms of David which spoke of Messiah and resurrection; They knew then what Jesus meant by His reference to Jonah when explaining His resurrection. They knew all this from Peter's sermon, he gave the Jews what they knew, their very own Holy Scriptures. The Son of God the Messiah is there on every page screaming out to them and Peter guided them on target like a lazer on target.
I dare not argue with the very Author of Salvation. He is the sheperd we are the sheep. The sheep hear His Voice and follow Him.
Peter explained that.
Romans 4:1What then shall we say was gained by Abraham, our forefather according to the flesh? 2 For if Abraham was justified by works, he has something to boast about, but not before God. 3 For what does the Scripture say? "Abraham believed God, and it was counted to him as righteousness."
He goes on to explain that Abraham was considered righteous because of his faith before he was circumcised. Paul says we are saved by grace through faith of Christ. Not faith in Christ.
Philippians 3:9 And be found in him, not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith:
Not faith IN Christ but the faith OF Christ. Its Christs faith instilled in us by which we can say yes to the free gift of salvation. Christ has already done that in us before we could possibly repent. Thats why putting repentance as a condition for salvation is error. The corrupt nature of man cannot change unless Christ has already done a work in that person.
Romans 8:7 Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be.
Christ must be at work for us to even be able to repent and that is a free gift.
Romans 3:24 Being justified freely by his grace through the redemption that is in Christ Jesus:
Just let go of anything you think you can do and understand it's Christ's work in you. It makes the awsome gift of salvation even that much more amazing. Credit and gratitude is due only to God.
Peter didn't know about the grace that was revealed to Paul...Paul didn't even know it for some time...And it was not taught at the beginning...
Doing works for repentance was prevalent...One couple was struck down dead because they with held information about some property...Another guy was told to sell everything that he had and give the money away...That doesn't happen under the gospel of grace by faith without works...