bor koro vayyachpereyhu vayyippol beshachas yifʿol
He has dug a pit and deepened it, and will fall into the trap he made.
RADAK
1. He has dug a pit, and graven it out...
repeating the idea in different words. And he says that he has dug a pit to cause me to fall into it, but he shall fall into it himself. He prophesies that Saul shall die by the sword.
2. And has fallen into the ditch which he makes:
a past tense in place of a future [prophecy]
Rabbi HIRSCH
1. He has dug a pit...
...and was about to hollow it out when he himself fell into that very blackness of destruction which he wanted to prepare for others.