Pigs prefer to wallow in clean mud, but if nothing else is available, they will frequently wallow in their own urine, giving rise to the notion that they are dirty animals.
But the more we search the Scriptures, the more we perceive, in this doctrine, the fundamental truth of the gospel - that truth which gives to redemption its character, and to all other truths their real power.
The weakness of ourselves and of our reason makes us see flaws in beauties by making us consider everything piece by piece.