Asalaam O Alaikum....
Jazak Allah for this thread brother...we really needed this....
Surah Az Zumar
(39:53) Say, "O My servants who have transgressed against themselves [by sinning],
do not despair of the mercy of Allah . Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful."
(39:54) And return [in repentance] to your Lord and submit to Him before the punishment (death and resurrection) comes upon you; then you will not be helped.
Despairing yourselves and making the sinners or deniers of truth (Kafirs) despair of the Mercy of Allah (swt) is a great sin.... we need to be extremely careful when we declare non Muslims as going to hellfire. By our words and actions and giving fatwas they will turn away from Allah (swt) and we will become a cause of their turning away, this way we will loose Allah's mercy....
This is a Hadith Qudsi (The words are God's but they are not in the Quran, they're narrated by the Messenger of Allah (saw). They hold great significance after the Quran)
On the authority of Abu Hurayrah (may Allah be pleased with him) that the Prophet (PBUH), from among the things he reports from his Lord (mighty and sublime be He), is that he said:
A servant [of Allah's] committed a sin and said: O Allah, forgive me my sin. And He (glorified and exalted be He) said: My servant has committed a sin and has known that he has a Lord who forgives sins and punishes for them. Then he sinned again and said: O Lord, forgive me my sin. And He (glorified and exalted be He) said: My servant has committed a sin and has known that he has a Lord who forgives sins and punishes for them. Then he sinned again and said: O Lord, forgive me my sin. And He (glorified and exalted be He) said: My servant has committed a sin and has known that he has a Lord who forgives sins and punishes for sins. Do what you wish, for I have forgiven you.
It was related by Muslim (also by al-Bukhari).
The above explains quite well that the Mercy of Allah (swt) is continuous and Forgiveness of His is continuous as long as he/she repent before their death
regardless of whatever sins they may have committed... or
however many times they had committed...
...But the condition is that they have to repent before their death. If they do it right at the moment of their death then there is no Forgiveness and Mercy....
Surah An Nisa
(4:18)
"repentance shall not be accepted from those who do evil deeds until their dying hour, and then say, 'Behold I now repent'; nor from those who die as deniers of the truth."....