1 Samuel 15:18

And the Lord sent thee on a journey, and said, Go and utterly destroy the sinners the Amalekites, and fight against them until they be consumed.

Cross-reference

1 Samuel 15:1 reminds Saul of his anointing by Samuel, establishing the authority behind the command to destroy Amalek.

Exodus 17:14 records God's decree to blot out Amalek; this verse commands Saul to carry out that judgment.

Leviticus 27:28 defines the law of 'devoted things' (herem) — the same concept God commands Saul to apply to the Amalekites.

Leviticus 27:29 specifies that humans devoted to destruction must be put to death — directly underlying Saul's mission against Amalek.

Joshua 6:21 records the total destruction of Jericho as a devoted thing — a parallel example of herem warfare commanded by God.

2 Kings 10:30 praises Jehu for executing God's judgment on Ahab's house — a parallel to Saul's commission, though Saul failed.