In a circular letter to the Northamptonshire Baptist Association in May 1785, Fuller offers some tremendous reasons for pursuing the study of Church History. Specifically he is writing about how to respond to the fact that the church is falling into sin and lethargy. This is his first way to begin to solve the problem.
This portion can be found in The Armies of the Lamb, pp. 105-106.”
First, let us recollect the best periods of the Christian church, and compare them with the present; and the best parts of our lown life, if we know when they were, and compare them with what we are now. A recollection of the disinterestedness, zeal and godly simplicity of the primitive Christians, and their successors in after-ages, millions of who, in Christ’s cause, loved not their lives unto death, would surely make us loathe ourselves for our detestable lukewarmness! As Protestants, let us think of the fervent zeal and holy piety of our Reformers–think what objects they grasped, what difficulties they encountered, and what ends they obtained! As Protestant Dissenters, let us reflect on the spirit and conduct of our Puritan and non-conforming ancestors. Think how they served God at the expense of all that was dear to them in this world, and laid the foundation of our churches in woods, and dens, and caves of the earth! Say, too, was their love to God more than need be? Is the importance of things abated since their death? Might not they have pleaded the anger and cruelty of the times in excuse for a non-appearance for God, with much more seeming plausibility than we can excuse our spirit of hateful indifference? O let us remember whence we are fallen, and repent!”
Working out Salvation with Fear and Trembling 