When we seek God, we will receive mercy  -  Isaiah 55:7

Let the wicked forsake his way, and the unrighteous man his thoughts: and let him return unto the LORD, and he will have mercy upon him; and to our God, for he will abundantly pardon.  

Isaiah commanded those who had forsook the right way and thoughts to return to God. Once the individual returned to God, He would give mercy and pardon.