Why the dates are approximate
The Bible often tells us how old someone was at a key moment, how long a king reigned, or which ruler was in power. It does not usually give a numbered year in the way we would today. So historians compare the Bible's own timeline with records from Egypt, Assyria, Babylon, Persia, Greece, and Rome.
That means some dates are firmer than others. The period of the kings can be linked to known ancient empires more easily than the lives of Abraham, Isaac, and Jacob. Faithful readers can differ over parts of the chronology without disagreeing about the people and events Scripture presents.
The patriarchs and Moses
Abraham is often dated roughly 2000 to 1800 BC, with Isaac, Jacob, and Joseph following over the next few centuries. Genesis gives Abraham's age when he left Haran, when Isaac was born, and when Abraham died, showing a real sequence of generations (Genesis 12:4; Genesis 21:5; Genesis 25:7).
Moses is commonly placed somewhere between about 1500 and 1200 BC. There is a genuine debate here. Some connect the Exodus to an earlier date, partly because 1 Kings counts 480 years between the Exodus and Solomon's temple. Others favour a later date based on how they read evidence from Egypt and Canaan. Scripture says Moses was eighty when he spoke to Pharaoh and lived to 120 (Exodus 7:7; Deuteronomy 34:7).
And it came to pass in the four hundred and eightieth year after the children of Israel were come out of the land of Egypt, in the fourth year of Solomon's reign over Israel, in the month Zif, which is the second month, that he began to build the house of the Lord.
Kings, prophets, and exile
David lived around 1040 to 970 BC, and Solomon ruled after him, roughly 970 to 931 BC. David reigned for forty years, first in Hebron and then in Jerusalem, while Solomon also reigned forty years (2 Samuel 5:4-5; 1 Kings 11:42).
After Solomon, the kingdom divided into Israel in the north and Judah in the south. Elijah's ministry fits roughly the ninth century BC. Isaiah served mainly in the eighth century BC, while Jeremiah began before Jerusalem fell to Babylon and continued through that devastating period, around the late seventh and early sixth centuries BC (2 Kings 17:6; Jeremiah 1:2-3).
Daniel was taken to Babylon during the exile and later served under Persian rule, so his life is often placed around 620 to 530 BC. His story spans the change from Babylonian to Medo-Persian power (Daniel 1:1-5; Daniel 6:28).
So this Daniel prospered in the reign of Darius, and in the reign of Cyrus the Persian.
Jesus and the first Christians
Jesus was probably born around 6 to 4 BC and was crucified around AD 30 or 33. The apparently odd BC birth date comes from the fact that the calendar later created around Jesus' birth was slightly miscalculated. Matthew places Jesus' birth during Herod's reign, and Luke anchors John the Baptist's ministry in the fifteenth year of Tiberius Caesar (Matthew 2:1; Luke 3:1-2).
Paul was likely born around AD 5 and died in the mid-60s, probably during Nero's rule. Acts places his conversion after Jesus' resurrection and follows his journeys across the eastern Roman world, ending with him under guard in Rome (Acts 9:1-5; Acts 28:30-31).
These estimates can help you see the sweep of the story. Still, read the people themselves, not just the dates. Abraham trusted God, David repented and worshipped, Jeremiah wept for his people, Daniel prayed in exile, and the risen Jesus changed Paul's whole life.
And Paul dwelt two whole years in his own hired house, and received all that came in unto him, Preaching the kingdom of God, and teaching those things which concern the Lord Jesus Christ, with all confidence, no man forbidding him.