Is it meant by the man who recites the Qur'an at night but does not act upon it during the day that he never acts upon it at all, or that he acts upon only some of it?

Among the reasons for severe torment on the Day of Judgment is rejecting the Qur'an by abandoning it and not acting upon it, and neglecting the obligatory prayers by sleeping through them, which indicates a lack of attention and turning away from it. However, whoever leaves something of that due to an excuse or inability is not included in this warning. A believer must follow the Qur'an and act upon it, for the Qur'an and its people who used to act upon it will be brought on the Day of Judgment as intercessors for their companion. The lesson lies in acting upon it and pondering over it, not merely in memorizing or reciting without understanding or application.