Did Hashem already save him?
Radak: When You will save me [I will pay the vows and thank You].
Malbim: I was saved from Pelishtim via Shmuel's promise.
Why does it say "ha'Lo Ragli mi'Dechi"?
Radak: "Ha'Lo" strengthens the matter, like I explained (refer to 56:9:3:3). You saved my foot from being pushed off more.
Malbim: I will not be pushed off from being in Eretz Yisrael, via Gad's promise.
What is "Lehis'halech Lifnei Elokim b'Or ha'Chayim"?
Radak: When I am in Galus and pushed off, I cannot engage in Hashem's ways. When You will save my Nefesh and I will return to Eretz Yisrael, I will join with Chachamim, learn and engage with them in ways of the Neshamah, which is Ohr ha'Chayim.
Radak (from Shocher Tov): Lifnei Elokim is Eretz Yisrael; b'Or ha'Chayim is Gan Eden.
Malbim: Lehis'halech Lifnei Elokim is the opposite of my foot being pushed off; b'Or ha'Chayim is the opposite of Nafshi mi'Maves.
