Ta’dîl-i arkân means remaining motionless for a while after becoming calm at five places in namâz, namely, at ruku’, at two sajdas, at qawma, and at jalsa. According to Imâm-i Abû Yûsuf, it breaks namâz to omit the ta’dîl-i arkân deliberately. However, according to the Tarafayn, that is, Imâm-i A’zam and Imâm-i Muhammad, even if it does not break namâz,it is wâjib to perform that namâz again as you have omitted the wâjib deliberately.
