In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Question to Imaam Abdul Azeez Bin Baaz [may Allaah have mercy upon him]: What is the intent behind the Messenger’s ﷺ statement when he spoke about the Ummah in the hadith: “All of them (the sects) are in the fire except one” and what is that one?. Also, will all the other 72 (deviant) sects be in the fire for eternity? Benefit us.
The answer: The prophet ﷺ said, “The Jews split into 71 sects, meaning all of them are astray and their affair ruined, except one. The Christians split into 72 sects, meaning all of them are astray and their affair ruined, except one. And this Ummah will split into 73 sects- all of them in the fire, except one. This one group is Ahlus Sunnah Wal Jamaa’a [those who firmly adhere to the authentic Prophetic Sunnah and are united upon that] – the companions of the Prophet and those who follow them exactly in faith, the adherents to pure Islamic monotheism and sound faith.
As for the other 72 sects that have been threatened with the fire, among them is one who is a disbeliever (ref a), among them is one who is a sinner and among them is one about whom it is established with clear evidence that he is an innovator in religious affairs. So, the one – among them – that dies in a state of disbelief (ref b) will be in the fire for eternity, the one that dies in a state of adherence to religious innovation that is lesser than major disbelief (ref c) or sins is under the will of Allah, while still threatened with the fire. So, based on this it is known that not all of them are disbelievers, but rather among them is a disbeliever and other than him among the sinners and the innovators in religious affairs. [Ref 1]
[Refs a and b]: NB: Takfeer – declaring that a Muslim left the fold of Islaam is a judgement that can only be given by the upright scholars and none else. https://www.manhaj.com/manhaj/articles/obkwf-takfir-and-the-excuse-of-ignorance-shaykh-saalih-al-fawzaan.cfm
[Ref c]: NB: All religious innovations are evil, but there are those that will exit a person from the fold of Islaam (Bida’atul Mukaffirah) and those that do not exit a person from the fold of Islaam (Bida’atul Mufassiqah). Al-Allaamah Rabee Bin Haadee Al-Madkhalee [may Allaah preserve him] was asked whether there is a difference between Bidah Al-Mukaffirah and Bidah Al-Mufassiqah; so he replied that there is Bidah Mukaffirah, such as rejecting the Ruyah (i.e. denying that the believers will see Allaah in the afterlife); rejecting Allaah’s Uluww [i.e. denying that Allaah is above his creation –Allaah ascended over the Throne in a way that benefits his majesty)]; invoking other than Allaah; offering slaughtered sacrifice (i.e. animals) to other than Allaah etc. These are affairs of Bidah Al-Mukaffirah (the bidah that is tantamount to disbelief). But we do not make Takfeer of the people who commit this type of Bidah until we establish the proofs against them. That is because some of them (i.e. the people who fall into these affairs) carry doubts and are far away from the era of Prophethood and its light (i.e. guidance). So they fall into the likes these innovations. Rejecting the Ruyah is disbelief; rejecting Allaah’s Uluww is disbelief; the saying that the Qur’aan is created is disbelief-major disbelief. But this person, -[who testifies that none has the right to be worshipped except Allaah and that Muhammad is the messenger of Allaah, and he prays, observes fasting, wants paradise and believes in that] -received the doubts of the people of falsehood, so he falls into the likes of these affairs (i.e. these innovations that are tantamount to disbelief). So we say to him: You have fallen into disbelief and the evidence is this and this, and we clarify for him. So if Allaah grants him Tawfeeq and he returns to the truth, then all praise is due to Allaah. But if not, we declare him a disbeliever after establishing the proofs against him. As for Bidah Al-Mufassiqah it is other than this (i.e. it is not at the level of that which is tantamount to disbelief)…
[A paraphrased excerpt. see http://www.rabee.net/ar/questions.php?cat=26&id=484 ]
Sins and Repentance:
Imaam Ibnul Qayyim [may Allaah have mercy upon him] said: Disobedience is the cause of being in shaytaan’s captivity and a prisoner of lowly desires. A disobedient person is always in the captivity of his devil, the prison of his lusts and leadership of his desires. He is a captive and a shackled prisoner. There is neither a captive whose state of affairs is more evil than that of a captive whose captor is his worst enemy, nor is there a prison more restricted than the prison of desires, and shackles that are more restrictive than the shackles of lust; so how can a heart that is a captive and a shackled prisoner follow the path to Allaah and the home of the afterlife? How can he follow a single path when the heart is shackled and stricken with harm from every angle as a result of the [severity] of its shackles? The likeness of the heart is that of a bird; it distances from harm whenever it flies high and surrounded by harm whenever it lands. It is reported in a hadeeth: ‘’Shaytaan is a wolf to a human being.’’ And just as an unprotected sheep in the midst of wolves is quickly destroyed, likewise if there is no protection from Allaah for the slave, it is inevitable that his wolf will prey on him.
He is protected by Allaah through Taqwaah (fear of Allaah). Taqwaah is a shield and shelter from Allaah between the person and his wolf; just as it is a shield against punishment in this life and the afterlife. Whenever the sheep is closer to its shepherd, it is safer from the wolf and whenever it is distanced from the shepherd, it comes closer to being destroyed. So the sheep is more protected when it is closer to the shepherd, for the wolf only takes away the [sheep, cattle] that are distanced and far away from the shepherd.
The basis of this affair is that whenever the heart is distanced from Allaah, then harm upon it is quicker, and whenever it is comes closer to Allaah, it is distanced from harm. Being distanced from Allaah is of various levels and some are more severe than others. Being distanced from [Allaah] through disobedience is greater than being distanced from [Allaah] through thoughtlessness; being distanced from [Allaah] through bidah is greater than being distanced from [Allaah] through disobedience, and being distanced from [Allaah] through hypocrisy and shirk is greater than all of that. [An Excerpt from ‘Ad-Daa’u Wad-Dawaa’u’ page 119-120]
Imaam Ibnul Qayyim [may Allaah have mercy upon him] also said: Sin and disobedience is something common in all the nations. It is something that has not cease to exist in the world amongst the Children of Aadam regardless of their different social classes- the common people, the ignorant ones, [the zuhhaad – those who choose to abstain from some of the lawful pleasures of the worldly life which one can do without], those desirous of it [i.e. the pleasures], the leaders and those under their rule. This affair of [sin and disobedience] is not something specific to this Ummah of Muhammad [peace and blessings of Allaah be upon him], such that [the Ummah] and its Prophet are [singled out] with rebuked as a result of that. Sin and disobedience does not negate belief in the Messengers, because it is possible for them to exist alongside belief in the Messengers. And although disobedience diminishes the perfection and completeness of belief in the Messengers, however it does not negate it.
Sins are wiped away through sincere repentance. Allaah forgives the slave when he repents, even if his sins fill the heavens and are of a great number. Allaah said: [قُلۡ يَـٰعِبَادِىَ ٱلَّذِينَ أَسۡرَفُواْ عَلَىٰٓ أَنفُسِهِمۡ لَا تَقۡنَطُواْ مِن رَّحۡمَةِ ٱللَّهِۚ إِنَّ ٱللَّهَ يَغۡفِرُ ٱلذُّنُوبَ جَمِيعًاۚ إِنَّهُ ۥ هُوَ ٱلۡغَفُورُ ٱلرَّحِيمُ – Say: O Ibaadee [My slaves] who have transgressed against themselves [by committing evil deeds and sins]! Despair not of the Mercy of Allaah, verily Allaah forgives all sins. Truly, He is Oft-Forgiving, Most Merciful. [39:53]
This is the right of the one who repents because repentance wipes away the sin after it [was committed]. Therefore, the one who repents from a sin is like one without that sin. Tawheed [pure Islamic montheism] wipes away sins, as [mentioned] in the Hadeeth Al-Qudsiy: ‘’O Son of Adam! If you were to meet Me with enough sins to fill the earth, whilst not associating anything with Me [in worship], I shall meet you with its equivalent in forgiveness.’’ Therefore, strong Tawheed wipes away the sins of the Muslims; but if punished for their sins, they will be removed from the fire as a result of their belief in Tawheed. As for the people of shirk and the disbelievers, their good deeds are nullified as result of the disbelief and shirk they are upon. They will neither meet their Lord with good deeds in order to obtain safety nor will they be forgiven any of their sins. Allaah [Glorified be He] said: [إِنَّ ٱللَّهَ لَا يَغۡفِرُ أَن يُشۡرَكَ بِهِۦ وَيَغۡفِرُ مَا دُونَ ذَٲلِكَ لِمَن يَشَآءُۚ – Verily, Allaah does not forgive (a person) the sin of associating partners with Him in worship (i.e. if one dies in that state without repentance), but He (Allaah) forgives (sins that are) lesser than that (i.e. lesser than shirk) to whom He pleases]. [4:48] [Source: An Excerpt from ‘Hidaayatul Hayaaraa Fee Ajwibatil Yahood Wan-Nasaaraa. Page 123-124. Slightly paraphrased]
Sayyid Al-Istighfaar –
With Brief Commentary By Imaam Abdul Azeez Bin Baaz and Imaam Ibnul Qayyim
(may Allaah have mercy on both of them)
 Sayyid Al-Istighfaar – [With Brief Commentary By Imaam Abdul Azeez Bin Baaz]
 Sayyid Al-Istighfaar – [With Brief Commentary By Imaam Ibnul Qayyim]
Ref: 1: paraphrased. see link below