By faith Abraham, when he was called to go out into a place which he should after receive for an inheritance, obeyed; and he went out, not knowing whither he went.
Hebrews 11:8 (KJV)
Living by faith involves acting on what God has told us to do. Sometimes we may be called to step out into the unknown, not knowing all of the details of the road we have been called to travel. Yet we may be certain that, step by step, God is faithfully leading us and guiding us into the manifestation of what He has promised.