The above was my answer to what God was doing pre-creation.
Satan/serpent in the Garden is a theme of Revelation in which John identifies them as one and the same. Not being a braintrust, I always assumed it was some kind of possession what with serpents (snakes) also being part of the animal creation.
And, would God pardon Satan?
Why not? He doesn't immediately destroy Him at the end, but rather locks him up for a 1000 years.
God, being Creator of "all that there is" - which includes time - is not delimited by any such thing as time, much less an arrow of time.
Or to put it another way, a thing is true because God says it. Time, whether a line, plane or volumetric, is irrelevant to God because He is not time-bound. We are.
And I beheld, and, lo, in the midst of the throne and of the four beasts, and in the midst of the elders, stood a Lamb as it had been slain, having seven horns and seven eyes, which are the seven Spirits of God sent forth into all the earth. - Revelation 5:6
For by one offering he hath perfected for ever them that are sanctified. - Hebrews 10:14
And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you. - Exodus 3:14
Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am. - John 8:58
As soon then as he had said unto them, I am [he], they went backward, and fell to the ground. - John 18:6