[Zechariah] said, "My Lord, make for me a sign." He said, "Your sign is that you will not speak to the people for three nights, [being] sound."
The Saheeh International Quran Translation
قَالَ رَبِّ ٱجْعَل لِّىٓ ءَايَةً قَالَ ءَايَتُكَ أَلَّا تُكَلِّمَ ٱلنَّاسَ ثَلَٰثَ لَيَالٍ سَوِيًّا[Zechariah] said, "My Lord, make for me a sign." He said, "Your sign is that you will not speak to the people for three nights, [being] sound."