Jesus' death til Pentecost

Hi peoples:   The longer one is a believer the less one thinks like a non believer. We allow things that we do not understand to pass. How many of us while reading a book or newspaper, we come upon a word for which we do not know the definition, but we do not miss a step. We continue reading. We can do that for a book or newspaper but not the Bible, but we do.   Example:   How was one "saved" from the time Jesus died (before he arose) and the Day of Pentecost? The Old Law was fulfilled and no longer in affect and if the kingdom (the New) was not established until Pentecost how was one saved? Jesus (the testator KJV) was dead; his testament (KJV), in force.    Jesus was around during 40 or so of those days but no matter the Old was gone and the New not yet established. Surely all those people in the city on Pentecost did not have access to Jesus' personal pronouncement of the forgiveness of their sins.   Don't think of it as answering another of my niggling questions, what will you say when a 'non believer' asks and why will you say it?