Tahajjud is an amazing Salat. Allah Taala mentions in the Holy Qur’an (meaning): Truly, rising by night (for prayer of tahajjud) is the most effective way to subdue (one’s self) and to make speech more upright.  Surely, in daytime, you have a lengthy work to do.  And remember the name of your Lord, and devote yourself to Him with exclusive devotion.(Sura Muzammil: 6-7)
It is clearly stated in this verse that rising for Tahajjud results in ‘effective-fight’ against the nafs (lower self)! In Sura Isra/Bani Israyeel, Tahajjud has been related to Maqame Mahmood, which would be a very special place for Beloved Nabi ﷺ. Sahih Hadith relates that Allah Taala’s Blessing attracts His servants in a special way at the time of Tahajjud. According to Hadith in Bukhari and Muslim, Allah Taala descendants at the sky of the world and calls upon His servants to fulfill their needs. The Muhaddiseen mentions, ‘Allah Taala’s descending’ is completely beyond our comprehension and accepting this fact submissively is divine knowledge. Our pious predecessors never argued or elaborated on these issues. However, it has been clearly mentioned in the Hadith that during the final one-third of night, Allah Taala’s Blessing pay attention to His servants and Allah Taala calls for supplication and forgiveness. Indeed, for an obedient servant and faithful believer it becomes much more difficult to lie on the bed and sleep than to wake up! He spontaneously wakes up at the call of his Lord and starts praying, calling, supplicating and reciting from the Holy Verses!
Haven’t we ever seen people passing nights through worldly tasks, entertainments and obligations? Actually when the matters of love and fear come up there is no barrier. The desire makes it easy to sacrifice everything. Pious people actually find immense ecstasy on meeting their Lord! Tahajjud is meeting the Lord in seclusion.