question #1 Sahih Muslim 823b, Book 6, Hadith 343 : What is the significance of the phrase ‘fahal min muddakir’ in Islamic teachings?

Ishaq is reported to have said on the authority of Aswad who quoted on the authority of ‘Abdullah b. Mas’ud that the Messenger of Allah (ﷺ) used to recite these words as (fahal min muddakir).