´It was narrated that Mus'ab bin Sa'd said:` "I prayed beside my father and I put my hands between my knees, and he told me: 'Put your hands on your knees.' Then I did that again and he struck my hands and said: 'We were forbidden to do that, and we were commanded to put our hands on our knees.'"
Hadith Referenceسنن نسائي / كتاب التطبيق / 1033
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:متفق عليه
➊ Abrogation (naskh) is permissible in the Shariah, that is, at first a command was given to perform a certain act, and later it was abrogated by another command. ➋ The reconciliation (tatbiq) has been abrogated. ➌ Placing the hands on the knees is legislated (mashru‘). ➍ During prayer (salah), a person can be informed that "do not do it this way, rather the Sunnah method is like this." ➎ According to one's ability, a wrong (munkar) should be stopped by hand.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 1033