'From the daily incidents of conjugal and domestic life, we learn that a heart of affection occasionally vehement, but superficial and transistory, may consist too well with a course of conduct, exhibiting incontestable proffs of neglect and unkindness. But the passion which alone the Holy Scriptures dignify with the name of Love, is a deep, not a superficial feeling; a fixed and permanent, not an occasional emotion. It proves the validity of its title, by practical endeavors to gratify the wishes and promote the interests of the object of affection. "If a man loves me, he will keep my sayings" [John 14:24]. "This is the love of God, that we keep his commandments" [2 John 1:6]. This therefore is the best standard by which to try the quality, or the quality being ascertained, to estimate the strength of the religious affections.'
William Wilberforce, A Practical View of Christianity, p.52.