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? Esther 4:14

There had been a decree passed against the Jews. They were to be attacked and destroyed. However, God had put someone in position to change this decree. He had put Esther in the palace. Mordecai is telling Esther that it was her time to act. He was telling here that God was going to deliver but she had to be willing to act. Many times God puts us in positions to do something for him but we have to be willing to act and trust Him