1)
Why does it say "Azreni... Hoshi'eni k'Chasdecha"?
1.
Radak: Like Your Chesed with other people, and so it was with me many times, so now, save me!
2.
Malbim: Yeshu'ah is greater than help. You will do so amidst Your Chesed, which does not consider merit of the recipient.