Quran

A liar tells lies because he hopes to gain a benefit or to avert harm from himself. Allah, the Almighty, is the Creator of harm and benefit, so to even think that a lie may occur in His speech is inconceivable. Al-Tabari: 8/593.
Question: Why is no one more truthful in speech than Allah?

Allah asserts that His word is of the highest level of truth. Anything that is said concerning belief, knowledge and deeds that is contrary to what Allah has told us is false, because it goes against the true and certain text, hence it cannot be true. Al-Saadi: 191.
Question: What is the difference between one who takes his beliefs and principles from the Quran and another who takes them from a different source?

Meaning: Why have you divided into two groups over the hypocrites, and not agreed to disavow them? This question shows disapproval and negation, and the speech is addressed to all believers, but the meaning of the rebuke is directed to some of them who were inclined to the hypocrites and defending them, while others opposed the hypocrites and disowned them. So, the believers were forbidden from division, and were commanded to be all on one path in disowning the hypocrites, since the signs of their hypocrisy and disbelief are quite clear. Al-Qasimi: 1/200.
Question: What is the duty that Allah called upon believers to do in dealing with hypocrites?

Allah has reverted the hypocrites to disbelief as recompense for their evil thoughts and insincerity toward His Messenger (r). Deeds lead to similar ones, so, good deeds bring more good deeds, and evil deeds result in worse deeds. Ibn Ashur: 5/150.
Question: Why has Allah reverted the hypocrites to disbelief?

This necessitates that you should not love them, because alliances and friendships can only stem from love. Moreover, it entails that you should hate them, and regard them as enemies, because the prohibition on anything is a command to do its opposite. Al-Saadi: 192.
Question: What does the divine command of prohibiting taking hypocrites as allies entail?

(If they turn away) meaning: They turn away from emigrating. This is a warning to them before are held accountable. Meaning: Inform them of this ruling, and if they reject it, then seize and kill them. This proves that if one does something that may constitute disbelief, he will not be held accountable for it until he is informed of its consequences. If he persists, then he must be prosecuted and given a chance to repent. Ibn Ashur: 5/152.
Question: For one who does something that may constitute disbelief, when should he be held accountable for it?

Allah, the Almighty, empowers the polytheists to fight the believers by enabling and strengthening them, either as a punishment and retribution when evil is spread and sins become apparent, or to test the believers, or to expiate their sins. Al-Qurtubi: 6/511.
Question: Sometimes, Allah empower the polytheists to fight the believers. Why?