With the merciful thou wilt show thyself merciful.
God does not forgive the unforgiving
You say that the desert is a desert, because no rain falls upon it; but this is only half the truth. No rain falls upon it because it is a desert. The heated air rushing up from its arid surface disperses the vapours that would descend in rain. Some moisture there must be on the earth, else there cannot be rain from heaven. So in your heart this forgiving disposition must be, else you cannot rejoice in the fulness of God’s forgiving grace. The pardon may wait in the sky for you, but it cannot descend to you until that spirit is in you which was also in Christ Jesus.