en_tn/1sa/13/14.md

your rule will not continue

This is a litotes that can be stated in the positive form. Alternate translation: "your rule will end soon" (See: rc://en/ta/man/jit/figs-litotes)

a man after his own heart

Here "heart" represents Yahweh's desire or will. The phrase "man after his own heart" is an idiom that means to be a person who does what Yahweh desires. Alternate translation: "a man who is the kind of person he wants" or "a man who will obey him" (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-idiom)