This (Krsna does not very readily grant perfection in devotional service) means that Krsna wants to see that a devotee is actually sincere and serious and that he does not have ulterior motives: Revision history
Diff selection: Mark the radio buttons of the revisions to compare and hit enter or the button at the bottom.
Legend: (cur) = difference with latest revision, (prev) = difference with preceding revision, m = minor edit.