Proverbs 18:21 (KJV): "Death and life are in the power of the tongue: and they that love it shall eat the fruit thereof."

Never speak about obstacles as though they are immovable. Rather, if you are feeling overwhelmed by what you're facing, keep your mouth shut. Then, go straight to God's Word and get His opinion on the matter. Read His promises concerning you; draw boldly into His Presence and ask Him for His wisdom, that He promises to give you without finding fault with you. Once His promises have filled your heart with faith, then open your mouth and begin speaking them over your circumstance. God always responds to our words of faith, and those words have the power to create what is naturally impossible. Don't use your mouth to complain or murmur, it only produces doubt and fear, which is the very thing the devil responds to. So instead of using your mouth to describe your mountain, use it to move your mountain! From the conviction of your heart, speak God's word concerning any situation you find yourself in and you will enjoy the fruit that comes from doing so.