וַיִּשְׁלַ֥ח דָּוִ֖ד מְרַגְּלִ֑ים וַיֵּ֕דַע כִּֽי־בָ֥א שָׁא֖וּל אֶל־נָכֽוֹן׃
David therefore sent out spies, and understood that Saul was come of a certainty.
Read kabbalistic (mystical) interpretation of I Samuel 26:4: and classical mystical sources.