William Wilberforce wrote in Real Christianity:
Measure your progress by your experience of the love of God and its exercise before men....
In contrast, servile, base, and mercenary is the notion of Christian practice among the bulk of nominal Christians. They give no more than they dare not withhold. They abstain from nothing but what they dare not practice. When you state to them the doubtful quality of any action, and the consequent obligation to refrain from it, they reply to you in the very spirit of Shylock, "they cannot find it it the bond."
In short, they know Christianity only as a system of restraints. It is robbed of every liberal and generous principle. It is rendered almost unfit for the social relationships of life,and only suited to the gloomy walls of a cloister, in which they would confine it.
But true Christians consider themselves as not satisfying some rigorous creditor, but as discharging a debt of gratitude. Accordingly, theirs is not the stinted return of a constrained obedience, but the large and liberal measure of voluntary service.
From: Passion and Purity by Elizabeth Elliot