Me too. All the time! I am my own worst critic. I can tear myself down better than anyone else, I know just the right words to make me stop before I begin. You can't do it, you're not good enough. Not qualified, a failure. It's impossible
Nothing is impossible the word its self says I'm possible - Audrey Hepburn
Related Article: Kissing Fear Goodbye and Making A Splash
The things which are impossible with men are possible with God. Luke 18:27 KJV
Yes, sometimes we will fail. Sometimes we will slip and come tumbling back down that mountain that we tried so hard to climb. Sometimes we get hurt, we will want to give up. But if it is where He wants you I can promise you it will be well worth all of the pain, all of the fear. All of the exhaustion.
With God all things are possible. Trust Him. He will always have your back. If He is pulling you toward the proverbial cliff perhaps it's to teach you that no matter where you are you haven't left the palm of his hand.
See, I have engraved you on the palms of my hands; your walls are ever before me. Isaiah 49:16 NIV