إن تجتنبوا كبائر ما تنهون عنه نكفر عنكم سيئاتكم وندخلكم مدخلا كريما
"If you avoid the great things you are forbidden, We shall cover over your lesser failings and admit you to an honoured place."
The concrete sense of the root: the side, the flank. Janb — the side; jānib — the side or aspect of a thing. And ijtanaba (Form VIII): to leave a thing to one side and walk on, to keep away from it.
The picture in the word is worth recording: to avoid a prohibition is to leave it aside and keep walking. The verb describes not a struggle but a distance.
The same root will return in this sūra at the thirty-sixth verse: wa'l-ṣāḥibi bi'l-janb — "the companion at your side". That one root should be used in two opposite directions, one of keeping away and one of nearness, is a fact that can be verified within the sūra.
The verse divides the prohibitions in two: kabāʾir (the great ones) and sayyiʾāt (the lesser failings).
And how the division is to be made is not stated in the verse. In classical exegesis there is a wide debate over the list and the definition of the kabāʾir; that list is not given in this commentary and no definition is preferred. The reason is the method's rule against issuing legal rulings.
What can be said from the text is this: the verse establishes a proportion. Avoiding the great ones brings the covering over of the lesser ones. The verse, that is, asks not for faultlessness but for a priority.
نُكَفِّرْ — root ك-ف-ر: to cover. The root was treated in detail in al-Baqara (the farmer covering the seed with earth). I rely on that treatment. And its use here in the direction of good is worth recording: the act of covering can, from the same root, name both denial and forgiveness.
مُّدْخَلًا كَرِيمًا — mudkhal: a place one enters. Karīm — root ك-ر-م: precious, generous, noble. The verse does not use an attribute belonging to the place; it uses an attribute belonging to a relationship.