But it is happened unto them according to the true proverb: this is added, to prevent the scandal that might arise from their apostacy; q.d. It is not to be wondered at that they are again entangled in and overcome by their former pollutions, when there never was a thorough change wrought in their hearts. Dogs and swine (beasts unclean by the law) they still were, under the greatest appearances of reformation, and such they now show themselves to be by their vile apostacy.
The dog is turned to his own vomit again: as dogs vomit up what is burdensome to them, but, still being dogs, and not having changed their natures by easing their stomachs, lick up their own vomit again; so these, under a fit of conviction, through the power of the word, disgorge those sins which burdened their consciences, but having thereby gotten some ease, and their old nature and love to their former lusts still remaining, they again return to the same sins they had for a time forsaken.
The sow that was washed to her wallowing in the mire: as swine, that naturally love the dirt and mire, if sometimes they be washed from it, yet, still retaining their former disposition, return again to it; so likewise these here mentioned, however they may be washed from the pollutions of the world, and by the preaching of the gospel brought off from their former ways of sin, and brought into a profession of holiness, yet, still retaining their old nature and corrupt dispositions, they are easily prevailed over by them, and so relapse into their former abominations.