The "fountain filled with blood drawn from Immanuel's veins" sounded interesting.

Vividly he saw the "sinners plunged beneath that flood" losing all their guilty stains.

It was entirely reasonable, and with an assumption of carelessness he glanced cautiously over his own body each morning to see if his guilty stains showed yet.

But who was Immanuel?
And where was this excellent fountain?
Then there was being "washed in the blood of the lamb," which was considerably simpler--except for the matter of its making one "whiter than snow." He was doubtful of this result, unless it was only poetry-writing which doesn't mean everything it says.

He meant to try this sometime, when he could get a lamb, both as a means of grace and as a desirable experiment.
But plunging into the fountain filled with blood sounded far more important and effectual--if it were only practicable.