Surah 20. Ta-Ha, Ayah 59

Lit., "the day of adornment" - possibly the Egyptian New Year's Day. The expression "your tryst" has the connotation of "the tryst proposed by you".

A great day of a Temple Festival, when the temples and streets were decorated, and people were on holiday, free from work. Moses makes this appointment in order to collect as large a number as possible, for his first duty is to preach the Truth. And he apparently did it with some effect with some Egyptians (xx. 70, 72-76), though the Pharaoh and his high and mighty officers rejected the Truth and afterwards paid the Penality.