Why is it said, "May you wear out what is new and live a praiseworthy life," to someone who is wearing a laundered old garment, not a new one, and what is said to someone who is wearing a new garment?

The prophetic tradition, "Wear new, live praiseworthy, and die a martyr" is a reprehensible and incorrect hadith. Abdur-Razzaq erred in it, and a number of the critical imams explicitly stated its reprehensibility, clarifying that the correct form of it is mursal (a hadith with a missing link in the chain of narration, specifically the Companion).

As for the meaning of "ghaseel" (غسيل), it refers to something that has been washed, i.e., a worn garment, and it is contrasted with "jadeed" (جديد), which means new and has not been worn before. It is recommended for someone who wears a new garment to be told, "May you wear it out, and may Allah Almighty replace it," or "May you wear it out and be given a replacement."