Tafsir of At-Takathur 102:7

"Then you shall surely see it" is a repetition for emphasis, and the particle thumma (then) is used to denote the superlative degree. It has been suggested that the first vision occurs when they see it from afar, and the second when they enter it or arrive at it. It is also suggested that the first is knowledge, and the second is witnessing and direct observation. It is further said that the intent of "you shall see Hell" repeatedly refers to eternity, similar to the dual form in His saying: "Then return your vision twice" (karratayn), though this is highly contrary to the apparent meaning.

"The eye of certainty" ('ayn al-yaqin) means the vision which is the very essence of certainty, for uncovering by way of vision and witnessing is above all other forms of uncovering; thus, it is most deserving of being called the "eye of certainty." Here, 'ayn signifies the "essence" (or self), similar to the usage in "Zayd came himself" (nafsuhu). It is an adjective for a suppressed verbal noun, meaning: a vision of the eye of certainty. The governing agent of this is "you shall see it." It has also been suggested that both preceding verbs compete for it, though there is a discussion regarding its application that I do not think is hidden from you.

"Certainty" (al-yaqin), linguistically, as stated by the Master of Support (Al-Sayyid al-Sanad), is knowledge in which there is no doubt. In technical terminology, it is the belief that a thing is such, with the belief that it cannot be otherwise, being a belief that corresponds to reality and is impossible to remove. Al-Raghib said: "Certainty" is an attribute of knowledge that stands above cognition (ma'rifah), discernment (dirayah), and their likes. One says "knowledge of certainty," but one does not say "cognition of certainty." It is the tranquility of the soul alongside the firmness of understanding.

The Master interpreted "certainty" as you have heard. Several interpretations from the People of Truth have been transmitted regarding it: "Knowledge of certainty" is what evidence provides of perceiving a thing as it is; "Eye of certainty" is what witnessing and unveiling provide; and they placed "Truth of certainty" (haqq al-yaqin) beyond that. By way of example, he said: Every rational person’s knowledge of death is "knowledge of certainty." When they witness the angels—peace be upon them—it is "eye of certainty." When they taste death, it is "truth of certainty." They have other interpretations besides these, and most of what they said is based on technical convention, so do not be heedless.

Ibn ‘Amir and al-Kisa’i recited la-tarawunnah (you shall see it) with a dammah on the ta’. Ali—may Allah ennoble his countenance—Ibn Kathir (in one narration), and ‘Asim recited the first la-tarawunna with a fatha and the second la-tarawunnah with a dammah. Mujahid, Ashhab, and Ibn Abi ‘Ablah recited both with a dammah. It is reported from al-Hasan and Abu ‘Amr—with a difference of opinion regarding them—that they converted the two waws into hamzahs. The justification for this is that they found the dammah on the waw burdensome, so they used the hamzah for ease, just as they did in the word wuqit (appointed time). The standard grammatical rule would dictate leaving the hamzah out, because the dammah is an accidental vowel due to the meeting of two quiescent letters, and thus it should not be counted. However, since it became a constant feature of the word such that it does not disappear, it resembled an original vowel, so they used the hamzah. They have even used the hamzah for accidental vowels that disappear when pausing, such as in ishtaraw al-dalalah (they purchased error); therefore, using the hamzah here is more appropriate.