In introduces a condition. Lam yadkhul al-qarinu Makkata negates entry into Makkah, with al-qarin as subject and Makkah as object.
Fa-qad sara rafidan states the legal consequence: sara is a defective verb and rafidan its accusative predicate. Bi-l-wuquf identifies the decisive standing. Repeating ʿalayhi sets out separate obligations.