The Family Of Imran - 3:41
"He said, "My Lord, give me a sign."He said, "Your sign is that you do not speak to the people except by sign for three days. Remember your Lord much, and think of Him morning and evening."
Related:
Mary/19:10
"Lord, give me a sign,"he said. "Your sign is that you will not speak to the people for three consecutive nights."
Mary/19:11
"And he went out from the temple among his people and gave them a sign, saying, "Think of him morning and evening."