Then the Lord asked Moses, “Who makes a person’s mouth? Who decides whether people speak or do not speak, hear or do not hear, see or do not see? Is it not I, the Lord? Now go! I will be with you as you speak and I will instruct you in what to say.”
Exodus 4:11 – 4:12
So for when you get tongue tied, you are afraid, you don’t know what to do,think, feel or say… remember to pray, because the lord is always with you.