Before the coming of this faith, we were held in custody under the law, locked up until the faith that was to come would be revealed.
OJBBut before Emunah came, we were being held in custody, being confined and guarded for the about-to-be-revealed Emunah.
TCENTNow before faith came, we were kept in custody under the law, confined until the faith that was to come would be revealed.
T4TBefore God revealed the good message about trusting in Christ, the laws [PRS] that God gave to Moses were confining/imprisoning us Jews [MET], as a prisoner in jail is confined. We were unable to escape obeying those [MET] laws. This happened in order that we might believe the good message concerning Christ, the message that God would reveal later.