Is there torment in the grave, or torment before the Reckoning? And why does Dr. Ali Mansour Kayali believe there is no torment in the grave, basing his view on Quranic verses?

The torment and bliss of the grave are established by texts from the Qur'an and Sunnah and by the consensus of the أهل السنة (Ahl al-Sunnah). This is not a matter for ijtihad (independent reasoning) or dispute. Whoever denies it has made a grave error. The verses of the Qur'an do not negate it; rather, they affirm it. Matters of religion and creed must be taken from scholars known for their piety and trustworthiness.