John Gill Commentary 1 Samuel 24:6

"And he said unto his men, Jehovah forbid that I should do this thing unto my lord, Jehovah`s anointed, to put forth my hand against him, seeing he is Jehovah`s anointed." — 1 Samuel 24:6 (ASV)

And he said unto his men
When he returned and brought the skirt of Saul's garment in his hand; or else he said this before that, though here mentioned, when they moved it to him to dispatch him, as he had a fair opportunity of doing it:

God forbid that I should do this thing unto my master, the Lord's
anointed ;
and which he could not think of but with detestation and abhorrence, since he was his sovereign lord and master, and he a subject of his, and was anointed by the order of God, and his person sacred:

to stretch forth my hand against him ;
to take away his life; to cut off the skirt of his garment gave him uneasiness; but to slay him, the thought of it was shocking to him:

seeing he [is] the anointed of the Lord ;
anointed by Samuel to be king, (1 Samuel 10:1) , by order of the Lord, (1 Samuel 9:17) .