There was a man who was highly proficient with computers. When he wanted to change what was stored in the computer and remove unwanted data from it he could do so, in a way that would make it virtually impossible to retrieve the old data.
It was lost for good.
His proficiency, along with the computer's powerful design made this possible. One would be entirely unable to recall unwanted data on that man's computer. Ability, desire and power made this happen.
There is a Being, a Person, who is infinitely more powerful than any known computer. Because of His power He can delete unwanted information from Himself. In addition He will not retrieve it because He desires to not recall things He, or we, would like forgotten.
As computers are in many ways unlike us, so the Father is infinitely unlike us. He promised He has deleted unwanted memories of our deeds from His memory base. Something we cannot fathom but is nonetheless as true as the power of today's computers.
"As far as the east is from the west,So far has He removed our transgressions from us." - Psalm 103:12
“For behold, I create new heavens and a new earth; And the former shall not be REMEMBERED or come to mind." - Isaiah 65:17
"No more shall every man teach his neighbor, and every man his brother, saying, ‘Know the LORD,’ for they all shall know Me, from the least of them to the greatest of them, says the LORD. For I will forgive their iniquity, and their sin I will REMEMBER no more.” - Jeremiah 31:34