The skill of living for God is not a natural power, one to which we are not taught but made; it is instead an acquired faculty, and therefore it certainly demands a rule to direct it, and in fact one that has been prescribed by God, as we taught just above. Over and above the life of Christ and one’s own conscience, we previously established that this rule is the Word of God, or Scripture. And as it is the norm for living, it is thus also a common complex of precepts and rules that apply to living. For this reason it is called the principium of theology. We will build our reflection on this point on the words from 2 Timothy 3:16–17

PETRUS VAN MASTRICHT, THEORETICAL-PRACTICAL THEOLOGY, VOLUME 1: PROLEGOMENA, 271.

For skill in theology is the habit of the whole person, by which he is brought to possess God and to act according to his will and for his glory. For this reason the whole person and all his parts are said to be sanctified (1 Thess. 5:23), but especially the will, which is the principium that commands all spiritual actions.

PETRUS VAN MASTRICHT, THEORETICAL-PRACTICAL THEOLOGY, VOLUME 1: PROLEGOMENA, 249.

The student has a theological goal set before him, not wealth, glory, pleasures, or leisure, but rather the glory of God, the edification of the church, and his own salvation.

PETRUS VAN MASTRICHT, THEORETICAL-PRACTICAL THEOLOGY, VOLUME 1: PROLEGOMENA, 238.

Therefore, first and foremost it must be recognized that theology’s supreme author and first source is: God (James 3:17), for which reason theology is the “wisdom of God”155 (1 Cor. 2:6–7) because it is first about God, and then from God; Christ, for which reason theology is called the “words of Christ”156 (1 Tim. 6:3); and the Holy Spirit, for which reason he is called “the Spirit of wisdom” (Isa. 11:2; Eph. 1:17). From these designations we gather that theology exists by the revelation of the Father (Matt. 16:17), the Son (John 1:18), and the Holy Spirit (2 Peter 1:21), by illumination for perceiving revealed truth (Eph. 1:18), and by guidance in the truth that has been perceived (John 16:13; Ps. 25:5; 143:10). Therefore, let us entreat him with the most fervent prayers (James 1:5; 1 Kings 3:9), that he would give the Spirit to us (John 16:13) and anoint the eyes of our minds with salve (Rev. 3:18), that thus we might see marvelous things in the law of God (Ps. 119:18, 27).

PETRUS VAN MASTRICHT, THEORETICAL-PRACTICAL THEOLOGY, VOLUME 1: PROLEGOMENA, 237.

Magistrates, who should know theology and should have the law before their eyes (Deut. 17:18–20; Josh. 1:8; Psalm 19), prescribe it for their subordinates (2 Chron. 17:7–9; Josh. 24:14ff.), protect it against enemies, as nursing fathers of the church (Isa. 49:23; 60:16) and as guardians of both tables of the law, and propagate it (Gen. 18:19).147 In sum they should, in all these ways, kiss Christ (Ps. 2:10–12), so that their polity becomes a theocracy, that is, a Christocracy.

PETRUS VAN MASTRICHT, THEORETICAL-PRACTICAL THEOLOGY, VOLUME 1: PROLEGOMENA, 234.

Who is obligated [to cast out false theology]?

This duty is incumbent on (1) preachers of Christian truth (Titus 3:10–11; Acts 15:2; Gal. 2:11, 14); (2) the magistrate (2 Kings 10:25), to whom it was formerly prescribed to resist false theology, even with capital punishment (Deut. 13:5; 18:20; 1 Kings 18:40); and (3) whoever has professed Christian truth (Matt. 7:15; Rom. 16:17; 2 Thess. 3:14; 2 Tim. 2:16–17; Titus 3:10–11; 2 John 10).

Reasons for these things Indeed, false theology must be resisted because it (1) strives to overturn the gospel of Christ (Gal. 1:7); (2) blasphemes the way of truth (2 Peter 2:2); (3) bewitches people so that they do not yield to the truth (Gal. 3:1); (4) ransacks churches (Acts 15:24; Gal. 1:7; 5:10, 12); (5) is destructive (2 Peter 2:2–3); and (6) is hateful to Christ (Rev. 2:6, 15).

PETRUS VAN MASTRICHT, THEORETICAL-PRACTICAL THEOLOGY, VOLUME 1: PROLEGOMENA, 232.

Christian theology is best defined as the doctrine of living for God through Christ.

Petrus van Mastricht, Theoretical-Practical Theology, Volume 1: Prolegomena, 208.