Son of Jephunneh the Kenizzite. This lineage is interesting because the Kenizzites were originally a Canaanite tribe (Gen 15:19). Caleb represents those who were fully grafted into Israel. He rose to become a leader of the tribe of Judah.
He was chosen as one of the 12 spies because he was a ruler. He went into the land, saw the grapes of Eshcol, and saw the sons of Anak (giants). He returned with a report of faith, not fear.
He was formed by Conviction. When the other ten spies melted in fear, Caleb silenced the people and said, "We should go up and take possession of the land, for we can certainly do it." (Num 13:30).