Jareer bin Abdullah reported,

Some bedouins came to the Messenger of Allah ﷺ wearing woolen garments. He saw the poor state they were in and that they had been struck by need, so he urged the people to give in charity. They were slow to respond, until distress could be seen on his face.Then a man from the Ansar came with a pouch of silver, then another came, then others followed in succession, until joy could be seen on his face.The Messenger of Allah ﷺ then said, "Whoever introduces a good practice into Islam that is acted upon after him, will have recorded for him a reward equal to that of everyone who acts upon it, without diminishing their rewards in the least. And whoever introduces an evil practice into Islam that is acted upon after him, will have recorded against him a burden of sin equal to that of everyone who acts upon it, without diminishing their burdens in the least."

عن جرير بن عبد الله قال

جاء ناس من الأعراب إلى رسول الله ﷺ، عليهم الصوف، فرأى سوء حالهم قد أصابتهم حاجة، فحث الناس على الصدقة فأبطؤوا عنه، حتى رئي ذلك في وجهه. قال: ثم إن رجلا من الأنصار جاء بصرة من ورق، ثم جاء آخر، ثم تتابعوا، عرف السرور في وجهه، فقال رسول الله ﷺ: من سن في الإسلام سنة حسنة، فعمل بها بعده كتب له مثل أجر من عمل بها، ولا ينقص من أجورهم شيء، ومن سن في الإسلام سنة سيئة، فعمل بها بعده، كتب عليه مثل وزر من عمل بها، ولا ينقص من أوزارهم شيء.