Read: Luke 1:26-38
And Mary said, "Behold, I am the servant of the Lord; let it be to me according to your word." And the angel departed from her. (Luke 1:38 ESV)
Mary trusted God implicitly. The angel Gabriel delivered the news about God's plan and Mary embraced it. We never read about her doubts, if she had any, her fears, or her hesitations. She embraced the fullness of God's plan for her life. Using language that in the original Greek text implies slavery. In other words, she was declaring to the angel that she was submitting herself to the will of God for her life in every possible way.
That is a boldness and bravery that many of us would really struggle with. It is born out of Mary's intrinsic trust in God. She was mighty in her faith. Her hope rested in The Lord and he used her obedience to orchestrate the salvation of mankind.
What might your "let it be" look like? What do you need to approach the Father with and say those three words? Jesus himself prayed that prayer in the Garden the night of his arrest. And how can we take our actions and back up our words? Yes, we should go to God as Jesus and Mary did, saying "let it be," but shouldn't we also be demonstrating the same willingness to lay down our lives through our actions?