Sentence:  And this is the excellency and perfection of a Christian, infinitely above the reach of the proudest moralists; this is the repentance of a Christian, whereby he makes up those defects which were most eminently notorious in the heathen; this is the impression of the humbling spirit, which proud heathen nature was never stamped with, for it was not so much their ignorance in which they offended God,—though that was also full of guilt, as hath been proved,—as their misusing of their knowledge to <WSD>ungainly</WSD> ends, as either ambition, superstition, or for satisfying their curiosity, as partly hath, and for the present needs not further to be demonstrated. 
Meaning of the word marked with <WSD> tags:  Unsuitable; unprofitable.