'Courageous' in the Bible

Only be strong and very courageous, to observe to do according to all the law, which Moses my servant commanded thee: turn not from it to the right hand or to the left, that thou mayest have good success whithersoever thou goest.

Therefore be ye very courageous to keep and to do all that is written in the book of the law of Moses, that ye turn not aside therefrom to the right hand or to the left;