Tafsir of Al-Isra 17:4-6

{And We decreed for the Children of Israel} We revealed to them a decreed revelation, meaning: a definitive and finalized judgment that they would inevitably cause corruption in the land and act with arrogance—that is, they would exalt themselves and commit transgression.

{In the Book} In the Torah.

{You will surely cause corruption} This is the answer to an implied oath. It is also permissible to treat the "decreed judgment" as having the force of an oath, making "you will surely cause corruption" its answer, as if He said: "And We swore that you will surely cause corruption." It has been recited as li-tufsudunna (passive voice) and wa-la-tufsudunna (with a fatha on the ta from fasada).

{Twice} The first: the killing of Zechariah and the imprisonment of Jeremiah when he warned them of God’s wrath. The second: the killing of John (Yahya) son of Zechariah and the attempt to kill Jesus son of Mary.

{Servants of Ours} It is also recited as ‘abidan lana. Generally, ‘ibad (servants) is used for God, and ‘abid (slaves) for people. They were Sennacherib and his soldiers; others say Nebuchadnezzar. Ibn Abbas said: Goliath. They killed their scholars, burned the Torah, destroyed the Temple, and took seventy thousand of them captive.

If you ask: How is it permissible for God to send disbelievers against them and empower them? I say: It means We left them to what they did and did not prevent them. Furthermore, God Almighty attributed the sending of the disbelievers against them to Himself, as in His saying: {And thus We make some of the wrongdoers allies of others for what they used to earn} (Al-An'am: 129), and like the supplication: "And cause discord between their words." He attributed the jaws—which is moving back and forth through the homes to cause corruption—to them. Thus, the destruction of the Temple and the burning of the Torah are part of the jaws attributed to them. Talha recited it as fahasu (with a ha). It is also recited as fajusu and khilala al-diyar.

{The promise of the first of them} It means the promise of the punishment for the first of them.

{And it was a promise fulfilled} Meaning: The promise of punishment was a promise that had to be carried out.

{Then We gave you back the turn} Meaning: The state and victory over those who were sent against you, once you repented and turned away from corruption and arrogance. It is said: This refers to the killing of Nebuchadnezzar, the rescue of the Children of Israel’s captives and wealth, and the return of sovereignty to them. Others say: It refers to David killing Goliath.

{More numerous in manpower} Than you were before. Al-nafir refers to those who go out with a man from his people. It is also said to be the plural of nafar, like ‘abid (slaves) and ma‘iz (goats).

{If you do good, you do good for yourselves; and if you do evil, it is for them. So when the promise of the second [time] comes, [they will] darken your faces and enter the mosque as they entered it the first time, and will destroy what they had taken over with [total] destruction.}