«وَالَّذِي أَحْلَى ذُرَاكُمْ»
By the One who has made your shelter pleasant and sweet.
Dhurā recalls the protective shelter mentioned earlier. Aḥlā (“made sweet”) gives hospitality the language of taste. The sweetness is figurative, describing the welcome rather than a literal flavour.
The oath begins courteously: before refusing a meal, the guest honours those offering it, making his reservation sound considerate rather than dismissive.