On the authority of Anas (may Allah be pleased with him) who said: I heard the Messenger of Allah (blessings of Allah and peace be upon him) say, “Allah, Blessed and Most High, said, ‘O son of Adam, as long as you call upon ME and put your hope in ME, I have forgiven you for what you have done and I do not mind. O son of Adam, if your sins were to reach the clouds of the sky and then you would seek MY forgiveness, I would forgive you. O son of Adam, if you were to come to ME with sins that are close to filling the Earth and you would then meet ME without ascribing any partners with ME, I would certainly [also] bring to you forgiveness close to filling it [the Earth]”
Recorded by al-Tirmidhi and he said, “It is a hasan sahih hadith”
There is none worthy of worship but Allah;
Put your hope in Allah.
This hadith gives the most hope to humans of all the hadith found in the sunnah. It demonstrates the great forgiveness of Allah and HIS mercy, so that no one should despair due to the great number of sins he has committed. However, at the same time, no one should be deceived or misled by their sins such that, due to his lackadaisical approach to sins, they end up creating a barrier between himself and the forgiveness of Allah and His mercy. In other words, forgiveness is still according to the Will of Allah and HE bestows it upon whomever He wills.
“O son of Adam”
This is a call from Allah to every human being. Allah is Most Compassionate, the Most Merciful He is calling out to all humans, with a call of forgiveness and mercy. Allah is willing to forgive. Neither the committing of sins by humans nor the forgiving of sins by Allah harms Allah in any way. Allah has decreed for Himself mercy and HE is ready to shower HIS grace and blessings upon all humans.
However, Allah only showers HIS forgiveness upon those who have performed the causes that lead to it, those who continue to call on HIM and put their hope in HIM while not associating any partner with HIM.
[Excerpt taken from a Commentary of the Forty Hadithof Al-Nawawi]