Assalam u Alikum Ustadh, Regarding Ahkam At Taklifiyyah, how do we differentiate between a decisive and non decisive command of the Messenger? May Allah preserve you on khair

Decisively meaning it is binding not like what is favored, so for example Allah commands it and makes a punishment for those that do not do it. Here we understand that this is decisive and binding otherwise why would there be punishment for not doing it?