Satan comes as a Serpent in the persons of false teachers, and by them labours to deceive us with error for truth. To defend us against this design, it is necessary that we be girt with the truth in our understanding.
I remember Tertullian, speaking of some heretics, as to their manner of preaching, says, "They teach by persuading, and do not by teaching persuade." Truth is loved and prized only by those that know it, and not to desire to know it is to despise it.
Every Christian should labour for an established judgment in the truth on account of the damning nature of false doctrines, remembering that false doctrines hunt for the precious souls of men, as well as any other sin. A corrupt judgment in foundation-truths kills as sure as a rotten heart.
This is not believed by some, who, though very strict in their lives, and apparently as tender in matters of morality as Lot was of his guests, yet are very loose in their principles and judgments, exposing them, as Lot later exposed his daughters, to be defiled with any corrupt doctrine that come to their door. They would make us think that in the matter of truth men played but at small game, and that their souls were not at stake, as in other sins. As if there were not such a question to be asked at the last day – what opinions we held? And whether we were sound in the faith? – in a word, as if false doctrine were an innocent thing. Yea, there be some that make as many roads to heaven as the Scriptures tell us there are ways to hell. Truths in many professing Christians' minds are not as stars fixed in the heavens, but are like meteors that dance in the air. They are not as characters engraven in marble, but writ in the dust, which every wind and idle breath of seducers deface. Therefore, humbly beg and established judgment of truth from God. But, lay this deep in thine heart, that God, who gives an eye to see truth, must also give a hand to hold it fast when we have it.
Keep therefore thy acquaintance with God, or else truth will not keep her acquaintance long with thee. "And having done all to stand, stand therefore, having thy loins girt with truth …"
William Gurnall - The Christian in Complete Armour.
