Bismillahir Rahmaanir Raheem

Tahajjud.

 
Tahajjud prayer! The great Tabeen scholar Hasan Al Basri (R.A) said while defining Tahajjud, whatever is performed after the Isha prayer as well as it is that salaah which is performed after some sleep. (pg76,vol 3.Ibn Katheer).
In the Holy Quraan Allah says “وَ مِنَ اللَّيْلِ فَتَهَجَّدْ بِهِ نَافِلَةً لَّكَ” (And in the night wake up for Salaah,an additional prayer for you.(17/79).
In this verse of the Quraan Allah highlights the greatness of the Tahajjud salaah.It is such a salaah that the Prophet (sallalaahu alaihi wa sallam) was particular about and greatly encouraged the Sahaba (R.A) to practice as well.
From a Fiqhi perspective there are varying rules levied on the performance of Tahajjud Salaah.Some place it as Fardh,others as Sunnatul Muakkada while another group attached the ruling of Nafl.
Fardh
During the early days of Islam when Surah Muzzamil was revealed,that was a time when the 5 times salaah was not yet made compulsory. Everyone was obligated to pray Tahajjud Salaah. When the Mi`raaj was completed and the Prophet (sallalaahu alaihi wa sallam) had been given the  5 times prayer the compulsion of Tahajjud was abrogated. However differences did arise, was it also abrogated on the Prophet (sallalaahu alaihi wa sallam), or did it remain compulsory on him.
It is explained that the correct and sound opinion is: when the obligatory status of Tahajjud was abrogated in the case of the Muslim Ummah ,it stood abrogated in the case of the Holy Prophet (sallalaahu alaihi wa sallam) as well .(Summarized from Ma aariful Quraan,vol 5 pg 535/536)
Sunnatul Muakkada
Whenever the Prophet (sallalaahu alaihi wa sallam) did an action constantly ,and never left it except under compulsion such an act gets the ruling of Sunnatul Muakkada. If its proven on the authority of an Islamic legal argument that it is special to the Prophet (sallalaahu alaihi wa sallam) and was not for the muslim Ummah then it will not be considered as Sunnatul Muakkada.
According to some Jurists Tahajjud is proven from uninterrupted Sunnah and there is no proof of it being restricted to the Prophet (sallalaahu alaihi wa sallam).Therefore some consider it preferable,weightier and worthier. .(Summarized from Ma aariful Quraan,vol 5 pg 535/536)
Nafl
Those Ulema who hold on to the position that it is Nafl explain that the consistency in its performance was a hallmark of the Prophet (sallalaahu alaihi wa sallam). .(Summarized from Ma aariful Quraan,vol 5 pg 535/536)
Despite the ruling, Tahajjud is established beyond doubt that it is from the Sunnah and should be practiced upon.Being a great believer lies in following the prince of both the worlds Muhammad  (sallalaahu alaihi wa sallam).Many times we become engulfed in the Fiqh of it, in saying something is only nafl in an aim to lower and degrade the action or use the ruling as an excuse not to practice. Sahaba never cared about rulings,they were hungry for the Aakirah and Allah, that anything which was a means of giving them that became part of their lives.
This is one practice that we should make an effort to revive.Before we sleep or the early morning after sleep.
DONT MISS THE OPPORTUNITY.