A warning for Christians who continue in sin?

Can you shed some light on Acts 17:30? Is this verse telling Christians, having received liberty from the Law through Jesus Christ’s death and resurrection, that we have no excuse for continued existence in sin?

Let’s look at the verse in context:

In Acts 17, Paul is preaching the gospel in Thessalonica. Because of his preaching, the unbelieving Jews become upset and attacked Paul. He escapes to Berea, and the same Jews proceeded to follow him there. This forces Paul to travel farther to Athens.

While he is waiting for Silas and Timothy in Athens, Paul continues to preach the gospel, both to the Jews in the synagogues and the Gentiles in the market place.

It’s important to note that Scripture says Paul’s spirit is provoked or angered by the idolatry he sees in Athens (Acts 17:16). This is Paul's state of mind when we find him in reasoning with the Gentiles in the marketplace and the Areopagus.

This sets the context for Paul’s speech to the unbelieving Gentiles:

Acts 17:24 “The God who made the world and all things in it, since He is Lord of heaven and earth, does not dwell in temples made with hands;
Acts 17:25 nor is He served by human hands, as though He needed anything, since He Himself gives to all people life and breath and all things;
Acts 17:26 and He made from one man every nation of mankind to live on all the face of the earth, having determined their appointed times and the boundaries of their habitation,
Acts 17:27 that they would seek God, if perhaps they might grope for Him and find Him, though He is not far from each one of us;
Acts 17:28 for in Him we live and move and exist, as even some of your own poets have said, ‘For we also are His children.’
Acts 17:29 “Being then the children of God, we ought not to think that the Divine Nature is like gold or silver or stone, an image formed by the art and thought of man.
Acts 17:30 “Therefore having overlooked the times of ignorance, God is now declaring to men that all people everywhere should repent.
Acts 17:31 because He has fixed a day in which He will judge the world in righteousness through a Man whom He has appointed, having furnished proof to all men by raising Him from the dead.

Regarding your question, the first thing to note is that Paul in not talking to Christians, but to unbelieving Gentiles. Therefore, this passage doesn’t have anything to say in respect to a Christians’ continued existence in sin. Rather, Paul is telling these Gentiles, who obviously practice idolatry (17:16, 22-23), how God will no longer overlook their idolatrous ways. Remember, Paul’s spirit is angered by all the idolatry he saw.

When Paul says God “overlooked the times of ignorance," he does not mean God will not hold them accountable for their sins when they die. Romans 3 tells us that no one is righteous and that all have sinned and fallen short of the glory of God. Romans 1 tells us that what may be known of God is evident in creation and within men’s conscience, yet men do not honor Him as God.

By “overlook," Paul simply means God did not punish men by judging them earlier and wiping them of the face of the Earth, as He was prepared to do. Rather, God tolerated sin in the world because He was waiting for a certain time in which He would display His righteousness. In this sense, they were “ignorant” because Christ had not yet come into the world, lived, died and been resurrected. Romans 3 puts it this way:

Rom. 3:21 But now apart from the Law the righteousness of God has been manifested, being witnessed by the Law and the Prophets,
Rom. 3:22 even the righteousness of God through faith in Jesus Christ for all those who believe; for there is no distinction;
Rom. 3:23 for all have sinned and fall short of the glory of God,
Rom. 3:24 being justified as a gift by His grace through the redemption which is in Christ Jesus;
Rom. 3:25 whom God displayed publicly as a propitiation in His blood through faith. This was to demonstrate His righteousness, because in the forbearance of God He passed over the sins previously committed;
Rom. 3:26 for the demonstration, I say, of His righteousness at the present time, so that He would be just and the justifier of the one who has faith in Jesus.

God “passed over” the sins previously committed when he withheld His judgement against humanity, and He did so because He was waiting for the time Christ would come into the world and demonstrate His righteousness. Now that Jesus has come, Paul is declaring that there is now no longer a barrier to God bring judgment upon the world for its sins.

In a sense, Paul was saying the world is living on borrowed time, and every day could be its last. Therefore, God requires us to repent if we are to avoid the coming judgment, because those who hear the gospel will be judged by their knowledge of Jesus. We know the gospel message is true, because God has raised Him from the dead. In this sense, those who hear the gospel have no excuse, because God’s righteousness has been made manifest to them.