"He went out, not knowing where he was going" (Hebrews 11:8)
In the Old Testament, a person's relationship with God was seen by the degree of separation in that person's life. This separation is exhibited in the life of Abraham by his separation from his country and his family. When we think of separation today, we do not mean to be literally separated from those family members who do not have a personal relationship with God, but to be separated mentally and morally from their viewpoints. This is what Jesus Christ was referring to in Luke 14:26).
Living a life of faith means never knowing where you are being led. But it does mean loving and knowing the One who is leading. It is literally a life of faith, not of understanding and reason - a life of knowing Him who calls us to go. Faith is rooted in the knowledge of a Person, and one of the biggest traps we fall into is the belief that if we have faith, God will surely lead us to success in the world.
The final stage in the life of faith is the attainment of character, and we encounter many changes in the process. We feel the presence of God around us when we pray, yet we are only momentarily changed. We tend to keep going back to our everyday ways and the glory vanishes. A life of faith is not a life of one glorious mountaintop experience after another, like soaring on eagles' wings, but is a life of day-in and day-out consistency; a life of walking without fainting (see Isaiah 40:31). It is net even a question of the holiness of sanctification, but of something which comes much further down the road. It is a faith that has been tried and proved and has withstood the test. Abraham is not a type or an example of the holiness of sanctification, but a type of the life of faith - a faith, tested and true, built on the true God. "Abraham believed God ..." (Romans 4:3).