1)
Why did he say "Ken Azamerah"?
1.
Rashi: Like You did good to me, so I will sing Your name, to pay my vow every day.
2.
Radak: When You will do to me this that I asked, when I will pay my vow every day in Eretz Yisrael, I will also sing Your name for the goods that You did to me.
3.
Malbim: According to the words of the vow, so I will sing Your name via paying my vow every day. I will sit the entire day in Beis Hashem, and there I will sing Your name and praise You constantly.
