God heard [Israel’s] groaning and remembered his covenant with Abraham, with Isaac, and with Jacob. Exodus 2:24
I will forgive their wickedness and remember their sins no more. Hebrews 8:12
God is omniscient, knowing everything in his universe that it is possible to know. God’s level of perfect knowledge is absolutely overwhelming, so much so that Paul praises God lavishly, “O, the depths of the riches of the wisdom and knowledge of God! … Who has known the mind of the Lord, or who has been his counselor?” (Romans 11:33-34) There is not the slightest piece of knowledge, no matter how insignificant, that escapes God’s mind. God has never learned anything, for he already knew it. Neither can God stop knowing something he once knew—God never forgets anything. In speaking of Israel’s terrible injustices to the poor and needy, God has sworn this solemn pledge: “I will never forget anything they have done.” (Amos 8:7)
Now one of the sweetest promises in the Bible is God’s promise of the New Covenant made to Jeremiah and quoted twice in the book of Hebrews: “I will forgive their wickedness and remember their sins no more.” (Jeremiah 31:34) How marvelous that concept is, especially when we consider how many and how great are our sins! To know that the God who has holy eyes and can never look upon evil (Habakkuk 1:13) is able to look on us with delight as though we have never sinned in our lives is astonishing. Yet the more we consider the actual language of the promise, the more challenging it becomes. Surely the omniscient God cannot actually forget our sins. Surely, he will always know the exact words we spoke, the sequence of actions we took, every moment of our lives on earth. His infinite mind does not become strangely contracted when it comes to the long record of the sins of his people.
"To know that the God who has holy eyes and can never look upon evil is able to look on us with delight as though we have never sinned in our lives is astonishing."
So how do we understand this? How does the omniscient God forget our sins? I believe his many “remember” statements concerning his people help us. For example, during the flood, Genesis 8:1 says, “God remembered Noah.” In the destruction of Sodom and Gomorrah, Genesis 19:29 says “God remembered Abraham and rescued Lot.” These statements are not meant in an absolute sense as though events suddenly brought Noah and Abraham back to his forgetful mind. Rather it is an “anthropomorphism,” making the infinite God’s mind and actions accessible to our finite human conceptions by human-like language applied to God. Similar to speaking of God’s hand, or arm, or eyes, or mouth… when God has no body parts. Therefore, God “remembering” Noah or Abraham or Israel means acting in accordance with his purposes for them. So, God “forgetting” our sins mean he does NOT act in accordance with them. As the scripture says, “He does not treat us as our sins deserve.” (Ps. 103:10) That is the rich blessing of heaven… forever God will act as though we have never sinned. We will be clothed in white robes totally covering our shameful deeds in the gift of perfect righteousness and provisional forgetfulness from a perfect God.