St Paul's work, in carrying out the dispensation of this mystery, was twofold. It was both external and internal. He was a "herald and apostle"; he was also "teacher of the Gentiles in faith and truth" (1 Tim. ii. 7). He had in the former capacity to carry the good tidings from one end to the other of the Roman empire, to spread it abroad as far as his feet could travel and his voice reach, and thus "to fulfil the gospel of Christ." But there was another, mental task, as necessary and still more difficult, which likewise fell to his lot. He had to _think out_ the gospel. It was his office to unfold and apply it to the wants of a new world, to solve by its aid the problems that confronted him as evangelist and pastor,--questions that contained the seed and beginning of the intellectual difficulties of the Church in future times. He had to free the gospel from the swaddling-bands of Judaism, to emancipate the spirit from the letter of a mechanical and legal interpretation. On the other hand, he had equally to guard the truth as it is in Jesus from the dissolving influences of Gentile scepticism and theosophy. Fighting his way through fierce and incessant opposition on both sides, the apostle Paul led the mind of the Church onwards and guides it still in the faith and knowledge of the Son of God. These noble epistles are the fruit and record of St Paul's theological work. Through them he has left a deeper mark on the conscience of the world than any one man besides, except the Master of truth who was more than man.
The apostle was not unaware of the vast influence he now possessed, and that must accrue to him in the future from the transcendent interest of the doctrines committed to his charge. There is no false modesty about this splendidly gifted man. It is his not only to "preach to the Gentiles the good news of Christ's unsearchable riches"; but more than that, "to bring to light what is the administration of the mystery that has been hidden away from the ages in God who created all things." The great secret was out while Saul of Tarsus was still a persecutor and blasphemer. But as to the _management_ and _dispensation_ of the mystery, the practical handling of it, as to the mode and way in which God would convey and apply it to the world at large, and as to the bearings and consequences of this momentous truth,--the apostle Paul, and no one but he, had all this to expound and set in order. He was, in fact, the architect of Christian doctrine.