A brother in the name of Allah

I heard al-Ridha ‘Ali ibn Musa, peace be upon him, say: "Whoever has been able to acquire a brother in the name of Allah, has indeed found a house in Paradise." He said: Abul Hasan al-Rahbi al-Nahwi recited the following verse by Al-Hajjaj ibn Yusuf al-Tamimi: "If a man lives for fifty years then he indeed is quite near the fountain of his return, And when you pass a day of your life, do not say I have passed, but say I have an observer over me! And when a decade elapses in which you lived, and are back to join in an ensuing decade, then you are a stranger." All praise to Allah, and His blessings upon our master Muhammad, the Prophet, and his pure progeny.