Muadh ibn Jabal

Muadh ibn Jabal (; 603 – 639) was a sahabi (companion) of the Islamic prophet Muhammad. Muadh was an "Ansar" of Banu Khazraj and compiled the Quran with five companions while Muhammad was still alive. He was known as the one with a lot of knowledge. He was called by Muhammad "the one who will lead the scholars into Paradise."
Biography.
Era of Muhammad.
Mu'adh accepted Islam before the Second pledge at al-Aqabah in submission before Muhammad. Nevertheless, he was one of those who took the pledge.
Muhammad sent Mu'adh as the governor of Yemen to collect zakat. When Muhammad sent Mu'adh to Yemen to teach its people about Islam, he personally bade farewell to him, walking for some distance alongside him as he set out to leave the city. It is said that Muhammad informed him that on his return to Medina, he would perhaps see only his masjid and grave. Upon hearing this, Mu'adh began to cry.
After Muhammad.
When Mu'adh returned to Medina, the Caliph was Abu Bakr. He eventually accompanied Usama ibn Zayd on the Syrian expedition, dying there in 18 Hijri, due to the Plague of 'Amwas.
Legacy.
The college for the study of Shariah law, at Mosul University in Iraq, is named after him.
Sayings.
Al-Bayhaqi narrated in Shu`ab al-Iman (1:392 #512-513), and so did al-Tabarani, that Mu`adh ibn Jabal narrated that Muhammad said: "The People of Paradise will not regret except one thing alone: the hour that passed them by and in which they made no remembrance of Allah." Ali ibn Abu Bakr al-Haythami in Majma al-Zawa'id (10:74) said that its narrators are all trustworthy (thiqat), while Suyuti declared it hasan in his Jami` al-Saghir (#7701).
Ibn al-Jawzi recorded in Siffatu Safwah that Mu'adh advised his son, "My son! Pray the prayer of he who is just about to leave and imagine that you might not be able to pray ever again. Know that the believer dies between two good deeds; one that he performed and one that he intended to perform later on."