Charles Ellicott Commentary 1 Samuel 26:10

"And David said, As Jehovah liveth, Jehovah will smite him; or his day shall come to die; or he shall go down into battle and perish." — 1 Samuel 26:10 (ASV)

David said furthermore. —David suggests three possible cases in which the Divine arm might strike the “anointed of Jehovah.” The first, the Lord shall smite him by some sudden death from disease—no doubt, the recent death of Nabal was in his mind; the second by what is termed “natural death;” and the third by some blow received in battle. The idea of an arrow winged by some unseen hand was evidently here in the speaker’s thoughts.