In the Reformed Pastor, Richard Baxter addresses one of the reason ministers are delinquent in their ministry of evangelism. In reality, this problem has not changed. Now, the fruit of unbelief does not manifest itself in neglect for the duty proper, but in neglecting the proper means of evangelism. Our weak faith is now made manifest when we dilute or distort the gospel in the process of evangelizing.
We are so weak in the faith, that this is the greatest impediment of all. Hence it is, that when we should set upon a man for his conversion with all our might, if there be not the stirrings of unbelief within us, whether there be a heaven and a hell, yet at least the belief of them is so feeble, that it will hardly excite in us a kindly, resolute, constant zeal, so that our whole motion will be but weak, because the spring of faith is so weak. O what need, therefore, have ministers for themselves and their work, to look well to their faith, especially that their assent to the truth of Scripture, about the joys and torments of the life to come, be sound and lively. (188.8.131.52)