1 Samuel 31:4
Then said Saul unto his armourbearer, Draw thy sword, and thrust me through therewith; lest these uncircumcised come and thrust me through, and abuse me. But his armourbearer would not; for he was sore afraid. Therefore Saul took a sword, and fell upon it.
The setting is the Philistine war at Gilboa, where Saul is fearful, wounded, and unable to fight or escape. Rather than be captured and abused by the uncircumcised enemy, he asks his armor-bearer to draw his sword and thrust him through. When the armor-bearer refuses to kill him, Saul takes a sword himself and falls upon it, taking his own life.
The armor-bearer refuses because he is sore afraid, and because he will not strike the Lord's anointed king. That death is self-murder, ending in dishonor and despair. It came to this because Saul set his own will above God's will and refused to put obedience to God first.