Allatheena yajtaniboona kaba-ira al-ithmi walfawahisha illa allamama inna rabbaka wasiAAu almaghfirati huwa (surah Najm: 32)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(53:32) on those who avoid grave sins *30 and shameful deeds, *31 even if they may sometimes stumble into lesser offences. *32 Surely your Lord is abounding in His Forgiveness. *33 Very well is He aware of you since He produced you from the earth, and while you were still in your mothers' wombs and not yet born. So do not boastfully claim yourselves to be purified. He fully knows those that are truly Godfearing.

Allazeena yajtaniboona kabaaa`iral ismi walfawaa hisha illal lamam; inna rabbaka waasi`ul maghfirah; huwa a`lamu bikum iz ansha akum minal ardi wa iz antum ajinnatun fee butooni umma haatikum falaa tuzakkooo anfusakum huwa a`lamu bimanit taqaa

*30) For explanation, see E.N. 53 of An-Nisa.
*31) For explanation, sec E.N. 130 of AI-An'am and E.N. 89 of An-Nahl.
*32) The word lamam as found in the original is used for a small quantity of something, or its slight effect, or its mere closeness, or its existence for a short time. This word is used to express the sense that a person did not commit an act but was very near to committing it.
On the basis of its usages some commentators have taken the word lamam in the meaning of minor sins. Some others have taken it in the meaning that a person should practically reach very near a grave sin but -should desist from actually committing it. Still others take it in the sense of a person's remaining involved in a sin temporarily and then desisting from it. And according to some it implies that a person should think of, or wish, or intend to commit a sin but should rake no practical steps towards it. In this regard, the views of the Companions and their immediate followers are as follows:
Zaid bin Aslam and Ibn Zaid opine, and a saying of Hadrat 'Abdullah bin 'Abbas also is to the same effect, that it signifies those sins which the people had committed in the pre-Islamic days of ignorance, then alter embracing Islam they refrained from them.'
Another view of Ibn `Abbas is, and the same is also the view of Hadrat Abu Hurairah, Hadrat 'Abdullah bin 'Amr bin 'As, Mujahid, Hasan Basri and Abu Salih, that it implies a person's being involved in a grave sin or indecency temporarily, or occasionally, and then giving it up.
Hadrat 'Abdullah bin Mas'ud, Masruq and Sha'bi say, and the same also has been reported from Hadrat Abu Hurairah and Hadrat 'Abdullah bin `Abbas in authentic traditions, that this implies a person's approaching the very point of a grave sin and crossing alI its preliminaries but then restraining himself at the final stage, e.g. a person goes out with the intention of stealing but refrains from it in the end, or has colse association with other women, but refrains from committing adultery. Hadrat 'Abdullah bin Zubair, `Ikrimah, Qatadah and Dahhak say that this signifies those minor sins for which no punishment has been prescribed in the world nor any threat of punishment held out in the Hereafter. Said bin al-Musayyab says that this implies one's thinking of a sin in the mind but restraining oneself from committing it practically .
These arc the different explanations which have been reported in the traditions from the Companions and their immediate followers. The majority of the later commentators and doctors of law and jurists arc of the opinion that this verse and verse 31 of Surah An-Nisa classify sins into two main kinds: the major sins and the minor sins, and these two verses give man the hope that if he abstains from the major sins and open indecencies, AIlah will overlook his minor errors. Although some distinguished scholars have also opined that no sin is minor and the disobedience of Allah is by itself a major sin, yet as stated by Imam Ghazali the distinction between the major and the minor sins is something which cannot be denied, for the sources of knowledge of the Shari'ah values and injunctions aII point to this.
As for the question, what is the distinction between the major and the minor sins, and what kinds of sins are major and what kinds of them minor ? we are satisfied that: "Every such act is a major sin which has been forbidden by a clear ordinance of the Divine Book and the Shari'ah of the Prophet, or for which AIIah and His Messenger have prescribed a punishment in the world, or have held out a threat of punishment in the Hereafter, or have cursed the one guilty of committing it, or given the news of infliction of punishment on those guilty of committing it. " Apart from this class of sins all other acts which are disapproved by the Shari'ah, come under the definition of minor sins. Likewise, the mere desire for a major sin, or an intention to commit it, also is not a major sin but a minor sin; so much so that even crossing all the preliminaries of a major sin does not constitute a major sin unless one has actually committed it. However, even a minor sin becomes a major sin in case it is committed with a feeling of contempt for religion and of arrogance against Allah, and the one guilty of it does not consider the Shari`ah that has declared it an evil worthy of any attention and reverence.
*33) That is, "The forgiveness for the one guilty of minor sins is not for the reason that a minor sin is no sin, but for the reason that AIIah Almighty does not treat His servants narrow-mindedly and does not seize them on trifling faults; if the servants adopt piety and abstain from major sins and indecencies, He will not seize them for their minor errors and will forgive them magnanimously on account of His infinite mercy."