Then Paul and Barnabas answered them boldly: “We had to speak the word of God to you first.  Since you reject it and do not consider yourselves worthy of eternal life, we now turn to the Gentiles.

Paul makes it clear.  THEY are deciding they are not worthy of eternal life.  God’s free gift is for all, but if you reject that gift, you are choosing not to be saved, to be justified, to be reconciled.  Rejecting the Gospel is actually choosing damnation for yourself.  Imagine going into eternity with that!