Turnbull's research into the history of preaching was not for purely historical purposes and still less for shallow anecdotal purposes. He was interested in learning how to preach, and he felt the masters showed him how. The Puritans and eighteenth century evangelicals were his special models. From them he learned the importance of a plain style and sturdy structure. He knew and appreciated that these ideals call for a certain commitment to preaching these heroes from the past were not afraid to give, a commitment characterized by serious study, solid thought and careful writing.

Related to this commitment is the Puritan conviction that the sermon is God's appointed means of working conversion in the hearer. In keeping with his Puritan mentors, Turnbull believed we should preach for a verdict. Thus he thought a plain style and a sturdy structure should be combined toward leading the hearer to an encounter with the living God through which grace is operative and whereby the human soul is moved to make a decision for Christ.

2. Turnbull was a lover of the preacher's task. The work of ministry invigorated him even more than history inspired him. Here we have in mind the aims God hopes to accomplish through the pastoral office and, more particularly, through the pastor God has called into ministry.

Proclamation ever receives the first place in Turnbull's estimation. The work of the pastorate is large, encompassing much by way of the sacraments, pastoral care of individuals, and the various demands of parish administration. But preaching comes first. It is Turnbull's perception that the pulpit should receive the minister's best efforts if not the bulk of his or her time. In keeping with the Scottish tradition in which he was raised, he places the minister's expository lecture at a weekly Bible class in a close second to preaching.

When he spoke of what sermons are to accomplish, Turnbull appealed to Acts 26.18: "To open their eyes, and to turn them from darkness to light, and from the power of Satan unto God, that they may receive forgiveness of sins, and inheritance among them which are sanctified by faith that is in me" (KJV). In classic expository fashion, he divided the passage into main points each of which signals the minister's aim when preaching: (1) to open eyes, (2) to turn persons, (3) to offer forgiveness, and (4) to confer an inheritance.

Thus far we have witnessed a strong evangelistic note in Turnbull's approach to the ministry and especially to preaching. It should come as no surprise, then, that he devoted a book to this subject. Ever the man of humility, he did not presume to write the whole thing but brought together some of the best minds on the various dimensions of evangelism and had them contribute chapters. He himself wrote only one, the last, which was something of a concluding encouragement to the reader. In it he uplifted models from the past and called for new vigor in proclaiming the good news:

If preaching were restored to its former state and given honor in all our churches, we would witness a revival of vital Christianity. The fault for the decline in the church lies in the downgrading of the Christian message, and here the pulpit must take responsibility. A strong pulpit makes a strong church.