1 Chronicles 10 13
Saul died because he was unfaithful to the Lord. He did not keep the Lord's commands, and he also went to consult a medium.
Compare with other 3 random translations
GW 1 Chronicles 10:13So Saul died because of his unfaithfulness to the Lord: He did not obey the Lord’s word. He asked a medium to request information ⌞from a dead person⌟.
AMP 1 Chronicles 10:13So Saul died for his trespass against the Lord [in sparing Amalek], for his unfaithfulness in not keeping God's word, and also for consulting [a medium with] a spirit of the dead to inquire pleadingly of it,
KJV 1 Chronicles 10:13So Saul died for his transgression which he committed against the Lord, even against the word of the Lord, which he kept not, and also for asking counsel of one that had a familiar spirit, to inquire of it;