Give ear, O God, and hear; open your eyes and see the desolation of the city that bears your Name. We do not make requests of you because we are righteous, but because of your great mercy.(Daniel 9:18)
That, I would say, is a fine attitude when we approach God for anything. Daniel here, is making it clear that it's not of his or God's nation Israel's righteousness that he is interceding, but because God is merciful and willing to heal, restore and bless.
We should harbor no doubts about God being merciful. He has been so from the beginning and will remain so always.
Regarding God's mercy towards his chosen people, Isaiah the prophet wrote:
In all their distress he too was distressed, and the angel of his presence saved them. In his love and mercy he redeemed them; he lifted them up and carried them all the days of old. (Isaiah 63:9)
It is because of this same mercy of God that mankind has found salvation through Jesus Christ.
Writing to Titus, the Apostle Paul speaks highly of the mercy of God.....But when the kindness and love of God our Savior appeared, he saved us, not because of righteous things we had done, but because of his mercy........(Titus 3:4, 5)
The Apostle Peter confirms this by writing......Praise be to the God and Father of our Lord Jesus Christ! In his great mercy he has given us new birth into a living hope through the resurrection of Jesus Christ from the dead.... (1 Peter 1:3)
So let us approach the throne of grace with confidence every day, because we serve a merciful God who is willing to heal, restore and bless us.