1)
What is "Ta'amech"?
1.
Radak: It is your counsel and words. This is like Targum Yonasan, your knowledge.
2.
Malbim: Your proper, true claims.
2)
Why did David give three Brachos?
1.
Malbim: He thanked Hashem for saving him, Avigayil's proper claims, and she herself was proper to spare her house.
3)
What is the meaning of "Kilisani"?
1.
Rashi: He held me back, like "Lo Yichleh Mimecha" (Bereishis 23:7).
4)
How do we understand "v'Hoshe'a Yadi Li"?
1.
Rashi: The prefix Mem in mi'Bo b'Damim applies also to this - Hashem stopped me from sinning with blood, and from my hand 'saving' (taking vengeance for) me.