Jesus said to Thomas after he saw the wounds on the Lord and believed: "You became a believer because you saw me. Blest are they who have not seen and have believed." So we who believe are blessed. The other known part is that God will always lead us to what's best for us because he loves us so much. The only unknown are the details, exactly how God is going to make things happen. And it is this unknown part that turns our faith journey into an adventure.
From Psalm 23: "Even though I walk in the dark valley I fear no evil; for you are at my side..." I love this verse. For me, it describes the true faith journey.