Atonement

Sorry if these have been already quoted, but here are five verses below that show God's mercy in the OT.

Deu 4:31 For the LORD thy God is a merciful God; he will not forsake thee, neither destroy thee, nor forget the covenant of thy fathers which he sware unto them.

Neh 9:31 Nevertheless for thy great mercies' sake thou didst not utterly consume them, nor forsake them; for thou art a gracious and merciful God.

Exd 34:6 And the LORD passed by before him, and proclaimed, The LORD, The LORD God, merciful and gracious, longsuffering, and abundant in goodness and truth

2Ch 30:9 For if ye turn again unto the LORD, your brethren and your children shall find compassion before them that lead them captive, so that they shall come again into this land: for the LORD your God is gracious and merciful, and will not turn away his face from you, if ye return unto him.

Neh 9:17 And refused to obey, neither were mindful of thy wonders that thou didst among them; but hardened their necks, and in their rebellion appointed a captain to return to their bondage: but thou art a God ready to pardon, gracious and merciful, slow to anger, and of great kindness, and forsookest them not.

Hope this helps you in your studies.
God Bless