«وَالْمَقَامُ يَقْتَضِي اعْتِنَاءً بِشَأْنِهِ»
The context requires special attention to the matter.
Some meanings deserve fuller expression because they are central in themselves, striking, alarming, subtle, or extraordinary. The second clause therefore brings the intended point into clearer prominence after the first has prepared the listener.
Not every repetition is redundant. One sentence can establish the general frame while another supplies the rhetorically decisive content. The communicative setting determines why this expansion is needed.