2/198 — Trade is not a sin
The word فَضْل here means provision and gain. Whether trading during the pilgrimage season spoiled the act of worship was disputed; the verse plainly does away with the question.
The pattern لَيْسَ عَلَيْكُمْ جُنَاحٌ is a pattern of licence repeated in the sūra, and it always does the same work: to remove an extra prohibition people have laid down of themselves. What was done for entering houses from behind at verse 189 is done here too.
فَإِذَآ أَفَضْتُم مِّنْ عَرَفَٰتٍ — ifāḍa: water overflowing and pouring from a place. The movement of the crowd is told as flowing water; the word will continue into the next verse.