I don't focus on sexual immorality, the world does. it's the most common sin around.
I would follow the entire law, with sacrifices and stuff, if not that the letters and the gospels say that all sacrifices are fullfilled in Christ.
I would follow the convictions if the gospels and the letters didn't say vengence belongs to Christ.
And, since christ is our only priest, only He needs to concern with the rules concerning priests.
Where faith enters into my viewpoint? By faith I accept the fact that God sent His son to die for my transgressions of the law, and by faith I accept the fact that I am cleansed from all sin, and that I've started a new life in Christ Jesus, and that my old sinfull nature is dead.
By faith I have recieved the spirit of sonship from the heavenly Father.
By faith, I have become convinced, that the way to please the Father is to follow His commands. And all I want is to please my father, and not myself.