Esther 4:14 says: For if thou altogether holdest thy peace at this time, then shall there enlargement and deliverance arise to the Jews from another place; but thou and thy father’s house shall be destroyed: and who knoweth whether thou art come to the kingdom for such a time as this?
(KJV).
The verse is spoken by Mordecai to Esther in Esther 4, urging her to approach the king on behalf of the Jews. Read it in context at Esther 4:14, or the full chapter at Esther 4.