What does 1 Samuel 15:12 mean?
After a night of mourning over Saul's sin and God's response, Samuel rises early the next morning to find the king and confront him. It seems, though, that Saul is not where Samuel expects him to be.The king and the Israelite army have traveled back from the battle against the Amalekites in the south, beyond Judah and Israel's southern border. Along the way, Saul stopped at a town called Carmel. This is located in Judah, south of Hebron. Saul set up a monument in his own honor at Carmel, likely to describe and celebrate his victory over the Amalekites. This was apparently a common practice among kings in the ancient Near East. It doesn't seem appropriate for Israel who is empowered entirely by the Lord (Deuteronomy 8:17–18). This battle was meant to enact God's judgment on the Amalekites. The Israelites were to entirely destroy everything the Amalekites had (1 Samuel 15:3). This was not intended to benefit Israel; the purpose was for God's people to be used as an instrument of His judgment (Exodus 17:14–16; Deuteronomy 25:17–19).
Samuel is told that Saul went to Gilgal after that. Samuel will find the king there (1 Samuel 15:13).