Sin cannot be simply forgiven. Of course if God wanted to, He didn't have to sacrifice anything, and could have simply declared our sins forgiven. But that would not have been just and right. Before the crucifixion, God required us to sacrifice animals in order to atone for sin. Sin was not something that could be simply wished away. Every action had a consequence, and each sin had a punishment if not correctly atoned for. God is infinitely holy and righteous, and must punish the sinner or law-breaker. His Law would not be right if it did not bear punishment in order for it to be Law. But as the world became more and more sinful, something had to be done. God foresaw this, and so He sent down His Son (God in flesh) to live a perfect life that was according to the Law and completely sinless. When this spotless life, God Himself, was sacrificed, it would atone for an infinite amount of sins. No more sacrifices would have to be made, and yet all forgiveness and repentance would still be in accordance with the Law, as the blood of Jesus would have atoned for each and every sin.
Sin can be very simply forgiven by a thought and a wish inside your mind to be forgiven. Because God is all forgiving. What can I say about a Loving and Beautiful God Who forgives us just like that?
Allah the Almighty has said: “O son of Adam, so long as you call upon Me and ask of Me, I shall forgive you for what you have done, and I shall not mind. O son of Adam, were your sins to reach the clouds of the sky and were you then to ask forgiveness of Me, I would forgive you. O son of Adam, were you to come to Me with sins nearly as great as the earth and were you then to face Me, ascribing no partner to Me, I would bring you forgiveness nearly as great as its.”
This is how we view God in Islam. Isn't this beautiful and more intimate than what you describe?
As Islam has its deep spiritual view, it's also a practical religion. Meaning, if you committed an offense against other human beings: we have to do
whatever needs to be done to rectify the offense (within reason) and asking pardon of the offended party. In addition to asking God's forgiveness.
We, human beings, have to do this and that but God doesn't have to do anything. We are the ones who have to sacrifice, to be purified from our deficiency and weakness. God is greater than this.
God is infinitely holy and righteous, and must punish the sinner or law-breaker. His Law would not be right if it did not bear punishment in order for it to be Law.
Actually He doesn't want to punish us, that is why He forgives us with a sincere intention inside our hearts or with a good deed and no matter how much our sins are. The Loving, Merciful and Forgiving God doesn't have to punish the sinner after asking for His forgiveness. And When we experience and have such a beautiful relation with a Forgiving and Merciful God like this, we ourselves will try to treat people and all the living being by these great qualities; forgiveness and mercy, although it can't be compared to those of God...
When this spotless life, God Himself, was sacrificed, it would atone for an infinite amount of sins.
By God, I don't understand how someone can possibly believe in this. God Himself was sacrificed?
No being should atone/pay for the sins of other people. This is against justice, this is against individual responsibility and accountability, this is against respecting our intellect that is capable of differentiating between good and evil and this is against the good nature in us that
motivate us to do good and ask for forgiveness.
"And every soul earns not [blame] except against itself, and no bearer of burdens will bear the burden of another." Holy Qur'an