1)
To whom should Hashem return Tzedakah?
1.
Rashi: To every Tzadik [Radak - like I did].
2)
How should Hashem return the Tzedakah?
1.
Malbim: The person should have an opportunity to do the Tzedakah again, just like here David was righteous and did not kill Sha'ul [when he could have, in the cave], and now the opportunity came a second time.
3)
What is the meaning of "Nesancha
1.
Radak, based on Targum Yonasan: It is as if says Nesancha
1
If it were Samuch, there would be a Patach under the Yud. (PF)