Hazrat Abu Huraira (may Allah be pleased with him) narrates that the Messenger of Allah (peace be upon him) said: "Whoever stands (in prayer) during (the nights of) Ramadan with faith and the intention of seeking reward, all his previous sins are forgiven." (Sahih Bukhari, Hadith No. 38)
Taraweeh prayers are Sunnah Mu'akkadah. Therefore, those who habitually abandon them without a valid excuse are considered sinful. It is important to note that the Khulafa Al-Rashideen, the Sahabah, the Tabi'een, the Tab'a Tabi'een, the Imams of Ijtihad, and the Salaf all consistently and diligently performed Taraweeh prayers. Hence, we should also pray Taraweeh with great diligence.
The Prophet (Peace be upon him) himself did not pray Taraweeh in congregation except for a few days. He feared that Taraweeh would be made obligatory upon his Ummah like other faraiz. However, the Messenger of Allah (Peace be upon him) has commanded us to follow the sunnah of the Khulafa Al Rashideen. He said that following the Sunnah of the Khulafa Al Rashideen is akin to following the Prophet's Sunnah itself, and that their obedience is equivalent to the obedience of the Prophet himself.
Therefore, when Hazrat Umar (May Allah be pleased with him) called upon all the people to stand in congregation for Taraweeh in the Holy month of Ramadan, with Hazrat Ubai Bin Ka'b as their Imam, not one Sahabi at the time could deny or speak a word against this practice. In this way, a sunnah that had been forsaken by the Prophet (Peace be upon him) himself for fear of it being made obligatory, was revived by Hazrat Umar (May Allah be pleased with him). And by the Grace of Allah, this Sunnah continues to be adhered to even today.

Issued By Darul ifta Al-Ikhlas, Karachi