"All" Includes Saints: Ambrosiaster on Romans 3:23

"since all have sinned and fall short of the glory of God..." (Romans 3:23)

This includes both Jews and Greeks. For all here includes even the saints in order to show that nobody can keep the law without faith. For the law was given in such a way that faith was also embedded in it. This faith looked toward a future salvation. Thus the death of Christ benefits everyone, because it has here in this world taught what is to be believed and observed, and in the future it will deliver everyone from hell. --Ambrosiaster