Explanation of the words of Imam al-Nawawi (may Allah have mercy on him) regarding what he quoted: "

The Shaykh : The author (may Allah have mercy on him) said, in what he quoted from Shaddad ibn Aws (may Allah be pleased with him), that the Prophet (peace and blessings be upon him) said: The wise one means the decisive person who seizes opportunities and takes precautions for himself so that days and nights do not pass him by in vain and he is lost.
This means the one who reckons with it and looks at what he did of the commanded things and what he left of the prohibited things. Did he fulfill what he was ordered to do? Did he leave what he was forbidden from doing? If he sees negligence in himself regarding an obligatory duty, he makes up for it if possible and performs it, or if he sees in himself a transgression of a forbidden thing, he stops it, feels remorse, repents, and seeks forgiveness.
And his saying means working for the Hereafter, because everything after death is part of the Hereafter. This is the truth and the wisdom: that a person works for what is after death, because in this world he is merely passing through, and the destination is what is after death. If he is negligent and the days pass him by and he wastes them in what does not benefit him in the Hereafter, he is not wise. The wise one is the one who works for what is after death.
And he becomes one who cares only about the matters of this world, following his soul's desires in being negligent of the commands, following his soul's desires in committing prohibitions, and then hoping for Allah's promises. He says, “Allah is Forgiving, Allah is the Most Merciful, and I will repent to Allah in the future, and I will improve my situation when I grow old,” and the like of these false hopes that Satan dictates to him. Perhaps he will reach that time, and perhaps he will not.
In this hadith, there is an exhortation to seize opportunities and not to waste any of one's time except in what pleases Allah (Mighty and Majestic). One should leave laziness, negligence, and mere hoping, for hoping benefits nothing, as al-Hasan al-Basri (may Allah have mercy on him) said: “Faith is not in hoping or in adorning oneself with it, but faith is what settles in the heart and is confirmed by deeds.” So we, O brothers, must seize the opportunity in everything that brings us closer to Allah, by doing the commands and avoiding the prohibitions, so that when we are presented to Allah, we are in the best possible state. We ask Allah to help us and you in His remembrance, His gratitude, and the excellence of His worship.