Tahajjud prayer is a voluntary prayer (Nafl). It is not Fard (obligatory) for the Muslim Ummah. If a person does not perform Tahajjud, there is no sin on them.
However, Tahajjud holds a very high status in Islam and was strongly emphasized for the Prophet ﷺ.
Evidence from the Qur’an
Allah says in the Qur’an:
“And during a part of the night, pray Tahajjud beyond what is incumbent on you; it may be that your Lord will raise you to a praised station.”
— (Qur'an 17:79)
Many scholars explain that this command was specifically obligatory for the Prophet ﷺ, not for the rest of the Muslims.
Evidence from Hadith
The Prophet ﷺ said:
“The best prayer after the obligatory prayers is the night prayer.”
— (Sahih Muslim)
This hadith shows that Tahajjud (night prayer) is among the most virtuous voluntary prayers, but it is still not obligatory.
Scholarly Opinion
Islamic scholars from the major schools of jurisprudence agree that Tahajjud is Nafl (voluntary) for Muslims. Performing it brings great reward and closeness to Allah, but leaving it does not bring sin.
Conclusion
So the correct understanding is:
Tahajjud is not Fard.
It is a voluntary (Nafl) prayer.
It was obligatory for the Prophet ﷺ, but recommended for the Ummah .
Not praying Tahajjud is not sinful, but praying it brings great reward and spiritual benefit.