To the end that (eis to einai). Purpose again as in Rom 4:11.
Sure (bebaian). Stable, fast, firm. Old adjective from bainō, to walk.
Not to that only which is of the law (ou tōi ek tou nomou monon). Another instance where monon (see Rom 4:12) seems in the wrong place. Normally the order would be, ou monon tōi ek tou nomou, alla kai ktl.