Except for those who repent, put things right, and make things clear. I turn toward them. I am the Ever-Returning , the Most Merciful. ( Surat al-Baqara, 2:160)
As stated earlier, humanity was created ignorant and ungrateful, and therefore is vulnerable to sins, mistakes, and weaknesses. This aside, Satan constantly tempts people and strives to plant vain desires and deviance in them. Yet, no matter how great one's mistakes and sins are, there is always a way out: sincere repentance and His ensuing forgiveness. For this reason, we should never lose hope, regardless of what we have done. In the Qur'an, Allah states:
Say: “My servants, you who have transgressed against yourselves, do not despair of the mercy of Allah. Truly Allah forgives all wrong actions. He is the Ever-Forgiving, the Most Merciful.” ( Surat az-Zumar, 39:53)
Meanwhile, there is a very important point we need to keep in mind:
Allah only accepts the repentance of those who do evil in ignorance and then quickly repent after doing it. Allah turns toward such people. Allah is All-Knowing, All-Wise. There is no repentance for people who persist in doing evil until death comes to them and who then say: “Now I repent,” nor for people who die as unbelievers. We have prepared for them a painful punishment. ( Surat an-Nisa', 4:17-18)
Clearly, Allah accepts the repentance of His sincere servants, for their regret and commitment to abandon their sinful behavior is real. Even clearer is the fact that the death-bed repentance of an unbeliever is meaningless. The Qur'an gives the example of the Pharaoh's insincere repentance:
We brought the tribe of Israel across the sea, and Pharaoh and his troops pursued them out of tyranny and enmity. Then, when he was on the point of drowning, he said: “I believe that there is no deity but Him in whom the tribe of Israel believe. I am one of the Muslims.” What, now! When previously you rebelled and were one of the corrupters? (Surah Yunus, 10:90-91)
And also toward the three who were left behind, so that when the land became narrow for them, for all its great breadth, and their own selves became constricted for them and they realized that there was no refuge from Allah except in Him, He turned to them so that they might turn to Him. Allah is the Ever-Returning, the Most Merciful. ( Surat at-Tawba, 9:118)
Were it not for Allah's favor to you and His mercy … and that Allah is Ever-Returning, All-Wise. ( Surat an-Nur, 24:10)
