Walk is used in the Bible to express the character of a person.  It’s how a person conducts his life and moral reputation in everyday matters.  So this verse in Isaiah shows us that if we abide in the Lord we’ll be able to attain God’s ultimate purpose in our life despite the evil that surrounds us.  It says we’ll be able to walk and not faint…that is not becoming fearful, our minds not becoming foggy.  So how do we walk in this broken world and not faint?  We ask God… as Jeremiah wrote, “This is what the Lord says: ‘Stand at the crossroads and look; ask for the ancient paths, ask where the good way is, and walk in it, and you will find rest for your souls.’ ”  There is only one good way.  After Moses had given the people the Ten Commandments he then exhorted them to, “Be careful to do what the Lord your God has commanded you; do not turn aside to the right or to the left.  Walk in all the ways that the Lord your God has commanded you, so that you may live and prosper and prolong your days in the land that you will possess.” (Deuteronomy 5:32-33)  There’s only one good way…and if we follow it…it will lead to righteousness and life.