Did David tell his men why he did not kill Sha'ul only after regretting that he cut the garment?
Rashi: No. Verses 5 and 6 are out of order. Once the Navi discusses cutting the robe, it finishes the matter, including his regret over this. After this it returns to tell what he previously told his men, why he would not kill Sha'ul.
Radak: Yes. When they saw the corner of the garment in his hand, they asked why he did not kill him, and David answered.
Why did he say "Meshi'ach Hashem" twice?
Malbim: To kill him is a sin against Hashem, for he is His Mashi'ach. It would also be a sin against Sha'ul, for he is still Adoni Meshi'ach Hashem - unlike David's men, who thought that Sha'ul's anointment had ceased.
