When God says something He does it. It is permanent; it will not change. God told His people He would be with them; leading them the whole way. It was a new way – uncharted territory for them.
Christians have the same promise from God. When we follow Christ, He will lead, guide, and protect. That is God’s promise to us. Note: God will lead and we are to follow.
(I recommend reading the whole chapter to get full understanding.)