There are some beautiful word-pictures in the Christian faith, unfortunately, not all of these word-pictures are Biblical in their origin.
For instance, you may have been told that God will throw our sins in the Sea of Forgetfulness when we confess our sins to Him. While there are many verses talking about forgiven sin, there is no Sea of Forgetfulness mentioned by name in the Bible.
A person on answers.yahoo.com had some brilliant insights.
Now before freaking out because this word-picture is not Biblical in origin, let's look at some passages in the Bible that does address sin, forgiveness, and forgetfulness.
God will pardon our sin, have compassion on us, walk over our sin, and cast our sins into the depths of the sea. (Micah 7:18-19) This one is the closest to the Sea of Forgetfulness, but it's a generic sea, not a named sea.
God is all-knowing. (1st John 3:19-20)
God wipes out our transgressions and chooses to not remember our sins. (Isaiah 43:25)
God will be known by us, forgive our sin, and remember our sins no more. (Jeremiah 31:34)
God will be merciful and remember our sins no more. (Hebrews 8:12 and 10:17)
Our sins will be cleansed (Isaiah 1:18)
God has removed our sins from us as far as the east is from the west (hint: they never meet). Psalm 103:12
God forgives us and shows lovingkindness. (Psalm 86:5)
Take heart, God promises to not remember our sins. He promises to throw them away and forgive us. That's a reason to celebrate, even if there is no specific sea of forgetfulness.