Almsgiving, fasting, and pilgrimage are not simply preserved as familiar labels. Their legal form establishes disciplined devotional responsibilities. Almsgiving concerns financial duty; fasting involves restraint within known limits; pilgrimage brings together prescribed rites.
A Qur’anic instruction may state the essential obligation while practical particulars are known through authorized explanation. Such concision is not a deficiency in the command. Rather, the foundational norm and its implementation belong to one connected system of instruction.