David is believed to have been twelve to sixteen years

[Mary Naeem]

David is believed to have been twelve to sixteen years of age when he was anointed as the king of Israel. He was the youngest of Jesse's sons and an unlikely choice for king, humanly speaking. Samuel thought Eliab, David's oldest brother, was surely the anointed one. But God told Samuel, "Do not consider his appearance or his height, for I have rejected him. The LORD does not look at the things people look at. People look at the outward appearance, but the LORD looks at the heart" (1 Samuel 16:7). Seven of Jesse's sons passed before Samuel, but God had chosen none of them. Samuel asked if Jesse had any more sons. The youngest, David, was out tending sheep. So they called the boy in and Samuel anointed David with oil "and from that day on the Spirit of the Lord came powerfully upon David" (1 Samuel 16:13).