“And they say, “The fire will most certainly not touch us for more than a limited number of days.” Say: “Have you received a promise from Allah for Allah never breaks His promise – or do you attribute to God something which you cannot know?” (Qur’an 2:80)

A recent picture published by Blogging Theology:

This reminded me of people who claim that the Ibadi school and it’s perspective on salvation is harsh.
“Oh wow I did this big sin and I don’t go to heaven.”
First. Our position is the position of Islam
Second.
The reason a person does not go to heaven is because they despaired of Allah’s mercy.
It is your disbelief in the mercy of Allah and indirect disbelief in Allah that dooms you.
Say: Oh my slaves who have transgressed against themselves (by committing evil deeds and sins)! Despair not of the Mercy of Allah, verily, Allah forgives all sins. Truly, He is Oft-Forgiving, Most Merciful” (Qur’an 39:53)
“Oh my sons! Go and search ˹diligently˺ for Joseph and his brother. And do not lose hope in the mercy of Allah, for no one loses hope in Allah’s mercy except the ungrateful disbelievers.” (Qur’an 12:87)
[He exclaimed]: “And who – other than those who have utterly lost their way -could ever abandon the hope of his Lord’s grace?” (Qur’an 15:56)
How do people disbelieve in the mercy of Allah (swt) and not having faith in Allah?
By refusing to repent for their sins. By refusing to reform themselves.
“They are also the ones who, when they have committed a shameful deed or wronged themselves, remember Allah and implore Him to forgive their sins – for who will forgive sins save Allah? – and do not persist knowingly in whatever they have committed.” (Qur’an 3:135)
“Rush toward forgiveness from your Lord and a Heavenly Garden as wide as the heavens and the earth, prepared for those who are mindful of Allah.” (Qur’an 3:133)
It was narrated from Abu Hurairah that the Messenger of Allah (saw) said:
“When the believer commits sin, a black spot appears on his heart. If he repents AND gives up that sin and seeks forgiveness, his heart will be polished. But if (the sin) increases, (the black spot) increases. That is the Ran that Allah mentions in His Book: “Nay! But on their hearts is the Ran (covering of sins and evil deeds) which they used to earn.” [83:14]
Source: (https://sunnah.com/ibnmajah:4244)
“But no! In fact, their hearts have been stained by all ˹the evil˺ they used to commit!
Undoubtedly, they will be sealed off from their Lord on that Day. Moreover, they will surely burn in Hell,
(Qur’an 83:14-16)
“But I am truly Most Forgiving to whoever repents, believes, and does good, then persists on true guidance.” (Qur’an 20:82)
“And whoever repents and does good has truly turned to Allah properly.” (Qur’an 25:71)
“O you who have believed, repent to Allah with sincere repentance. Perhaps your Lord will remove from you your misdeeds and admit you into gardens beneath which rivers flow on the Day when Allah will not disgrace the Prophet and those who believed with him. Their light will proceed before them and on their right; they will say, “Our Lord, perfect for us our light and forgive us. Indeed, You are over all things competent.”(Qur’an 66:8)
Most Muslims today unfortunately believe unrepentant sinners can go on living in sin and than go to heaven and that many believers will spend brief sojourn in hell before going to heaven. As regards major sins; Rape, killing children, not praying. No worries just say “There is no god but Allah” will get one into heaven.
May Allah (swt) guide us. May Allah (swt) forgive us.