Just as in seeing the rainbow God will "remember" His covenant to never again send a flood to destroy all flesh, so in the covenant in Christ's blood God "remembers" not to treat believers as their sins justly deserve.

"When I bring clouds over the earth and the bow is seen in the clouds, I will remember my covenant that is between me and you and every living creature of all flesh. And the waters shall never again become a flood to destroy all flesh." Gen 9:14-15

"He does not treat us as our sins deserve or repay us according to our iniquities" (Ps. 103:10,)

"For by a single offering he has perfected for all time those who are being sanctified.

And the Holy Spirit also bears witness to us; for after saying,

“This is the covenant that I will make with them
after those days, declares the Lord:
I will put my laws on their hearts,
and write them on their minds,”

then he adds,

“I will remember their sins and their lawless deeds no more.”

Hebrews 10:14-17