Tafsir of Hud 11:86

(That which Allah leaves for you is best) Ibn Abbas said: Meaning, that which He, glory be to Him, leaves for you of lawful wealth after giving full measure is better for you than what you gather through cheating, for that [cheating] is scattered dust, or rather, it is pure [evil], even if you claim it is good.

(If you are believers) Meaning, on the condition that you believe, since with disbelief there is no goodness in anything at all; or, if you are those who believe me in what I say to you. In another narration from the "Scholar" [Ibn Abbas], he interpreted "that which remains" (al-baqiyyah) as provision. Al-Rabi’ said: It is His, the Exalted’s, commandment. Muqatil said: It is His reward in the Hereafter. Al-Farra’ said: It is mindfulness of Him, the Almighty and Majestic. Qatadah said: It is His storehouse. Al-Hasan said: It is His, glory be to Him, obligatory duties.

Ibn Atiyyah claimed that the wording of the verse does not yield all these [interpretations], and that its meaning is simply "that which is kept," derived from what was narrated from Ibn Jurayj, who said: The meaning is "Allah, the Exalted, keeping the blessings for you is better for you than what is obtained from the deficiency caused by giving short measure." In any case, the response to the conditional clause is omitted, indicated by what precedes it, according to the view of the majority of the Basrians, which is the correct view.

Ismail bin Ja’far narrated from the people of Medina the reading of (baqiyah) with a light ya. Ibn Atiyyah said: It is a [known] dialect. Abu Hayyan said: The rule for the description of the intransitive verb is to be on the pattern of fa'ilah, such as shajiyat al-mar'ah fahya shajiyah. If the ya is doubled, it is on the pattern of fa'il for intensification. Al-Hasan read it as taqiyat Allah with a ta’, meaning His, glory be to Him, piety and mindfulness that turns one away from sins.

(And I am not a guardian over you) I do not protect you from foul deeds, nor do I record your deeds for you to requite you for them. I am only a sincere warner who conveys the message; I have offered an excuse now that I have warned you, and I have not spared any effort. Or, [it means]: I am not one who preserves for you the blessings of Allah, the Exalted, if you do not abandon your evil conduct.