God furnished undeniable proof of the fact that what Jesus endured in His suffering and death on the cross was fully adequate in atoning for our sins by raising Him from the dead.
this man delivered up by the predetermined plan and foreknowledge of God, you nailed to a cross by the hands of godless men and put Him to death. And God raised Him up again, putting an end to the agony of death, since it was impossible for Him to be held in its power.
Acts 2:23-24
God has been, and continues now to declare to all men that He has provided His own son as the perfect payment in full for our sin. God is declaring to sinners that our only legitimate hope for deliverance from His eternal wrath is for us to put our trust in Jesus as the only and adequate remedy for our sin. God is instructing sinners to repent and believe in the Lord Jesus Christ.
how I did not shrink from declaring to you anything that was profitable, and teaching you publicly and from house to house, solemnly testifying to both Jews and Greeks of repentance toward God and faith in our Lord Jesus Christ.
Acts 20:20-21
It is not the act of turning from sin and from all other means of attaining the eternal favor of God, it is not the act of coming to Jesus that saves us - it is Jesus Himself, and it is Jesus alone. Faith is what brings us in confidence to Jesus alone for deliverance from sin - from sin's present power over us, from sin's future, just, and eternal penalty, and finally even from sin's presence when we are brought into the presence of our Lord forever.
But now apart from the law the righteousness of God has been manifested, being witnessed by the law and the prophets, even the righteousness of God through faith in Jesus Christ for all those who believe; for there is no distinction.
Romans 3:21-22
nevertheless knowing that a man is not justified by the works of the law but through faith in Christ Jesus, even we have believed in Christ Jesus, that we may be justified by faith in Christ, and not by the works of the law; since by the works of the law no flesh shall be justified.
Galatians 2:16
Therefore the law has become our tutor to lead us to Christ, that we may be justified by faith. But now that faith has come we are no longer under a tutor. For you are all sons of God through faith in Christ Jesus.
Galatians 3:24-26
God brings the good news of His perfect and only provision for sin to sinners as a blessed invitation and as a solemn command. When we come by faith to Jesus for salvation we are accepting an invitation from God, but we are also submitting to Him in humble obedience. God is beseeching and also commanding sinners everywhere to repent, and to put their trust in His Christ.
Therefore having overlooked the times of ignorance, God is now declaring to men that all everywhere should repent.
Acts 17:30
And this is His commandment, that we believe in the name of His Son Jesus Christ, and love one another, just as He commanded us.
1 John 3:23