ISB ~ 1 Timothy 1 v8

the law:The Torah or Law of Moses is “good” because it promotes virtue and prohibits vice (Rom 7:12, 16). Since many of the sins in the following verses are direct violations of the Decalogue (Ex 20:1-17), it is clear that the moral precepts of the Old Covenant are carried over into the New and, in Paul’s mind, are part of what constitutes “sound doctrine” (1 Tim 1:10). This is consistent with his teaching elsewhere in Rom 13:8-10, 1 Cor 7:19, and Gal 5:14.

lawfully:i.e., according to its true intent. Improper use of the Law was made by false teachers, whose useless conjectures spread confusion instead of religious conviction among believers. The purpose of the Torah is not to satisfy our curiosity but to encourage justice, mercy, and faith (Mt 23:23) (CCC 1962).

• The person who thinks he understands the Scriptures but is unable to build up the double love of God and neighbor does not truly understand them (St. Augustine, On Christian Doctrine 1, 36).