Narrated Abdullah ibn Umar:
I went to Allah's Apostle (peace_be_upon_him) in the morning and he heard the voice of two persons who had an argument with each other about a verse. Allah's Apostle (peace_be_upon_him) came to us (and) the (signs) of anger could be seen on his face. He said: Verily, the (peoples) before you were ruined because of their disputation in the Book.
Narrated Abdullah ibn Mas'ud:
Allah's Apostle (peace_be_upon_him) said: ruined were those who indulged in hair-splitting. He (the Prophet) repeated this thrice.
Narrated Jarir ibn Abdullah:
Some desert Arabs clad in woollen clothes came to Allah's Apostle (peace_be_upon_him). He saw them in a sad plight as they had been hard pressed by need. He (the Holy Prophet) exhorted people to give charity, but they showed some reluctance until (signs of) anger could be seen on his face. Then someone from the Ansar came with a purse containing silver. Then came another person and then other people followed them in succession until signs of happiness could be seen on his (sacred) face.
Thereupon Allah's Apostle (peace_be_upon_him) said: He who introduced some good practice in Islam , which was followed after him (by people), will be assured of a reward like those who followed it, without their rewards being diminished in any respect. And he who introduced some evil practice in Islam, which was followed subsequently (by others), he will be required to bear the burden like that of those who followed this (evil practice) without theirs being diminished in any respect.
Narrated AbuHurayrah:
Allah's Apostle (peace_be_upon_him) said: He who called (people to righteousness, there would be reward (assured) for him like the rewards of those who adhered to it, without their rewards being diminished in any respect. And he who called (people) to error, he shall have to carry (the burden) of its sin, like those who committed it, without their sins being diminished in any respect.