John Gill Commentary 1 Samuel 18:9

"And Saul eyed David from that day and forward." — 1 Samuel 18:9 (ASV)

And Saul eyed David from that day and forward .
] Instead of looking pleasantly, and with a smile, upon him, as a courtier and favourite, he was justly entitled to by his gallant behaviour, he looked at him with a sour, ill natured look; he looked at him with an evil, spiteful, malicious, and envious eye; or he diligently watched and observed all his motions and actions, whether they tended to disloyalty and treason, to dethrone him, and take the kingdom to himself, which he was suspicious of; he laid wait for him, as the Targum, and laid snares too, as the following history shows.