Musnad Ahmad 770:49

Sufyan narrated to us, from ‘Asim ibn Abi al-Najud, from Abu Wa’il, from Jarir, that a group of Bedouins came to the Prophet, may Allah bless him and grant him peace, wearing torn garments. The Messenger of Allah, may Allah bless him and grant him peace, encouraged the people to give charity, but they were slow to do so, until that was seen on his face. Then a man from the Ansar came with a piece of gold and placed it down. The people followed one another until that was recognized on his face. He said: "Whoever initiates a good practice, and it is acted upon after him, he will have its reward and the like of the reward of those who act upon it, without their rewards being diminished in the slightest. And whoever initiates a bad practice, and it is acted upon after him, he will bear its burden and the burden of those who act upon it, without their burdens being diminished in the slightest."