Doctrine is the armor of God

When we continually search works of Christian doctrine - as God's elect - we are drawn by the fact that doctrine is the armor of God. We're looking for sound armor, and for explication and elucidation of sound armor. We value sound armor.

This famous John Owen quote I've had in the right-hand margin gets at it:

"When the heart is cast indeed into the mould of the doctrine that the mind embraceth - when the evidence and necessity of the truth abides in us - when not the sense of the words only is in our heads, but the sense of the thing abides in our hearts - when we have communion with God in the doctrine we contend for - then shall we be garrisoned by the grace of God against all the assaults of men." - John Owen

Doctrine is practical. It effects the believer internally. To be God-centered rather than man-centered for instance is an effect of doctrine on one internally. Again I speak of God's elect who have the Spirit and can discern true doctrine and be affected by it.

When a false teacher argues, for instance, for works righteousness (under whatever name or guise) they are arguing for walking onto the battlefield wearing wax armor and carrying a cardboard shield and sword.

They are also arguing in favor of the continued internal tyranny of vanity, worldly pride, and rebellious self-will which are the chains the devil keeps fallen man in in the bondage and darkness of his kingdom.

Bad doctrine feeds and keeps alive the Old Man nature.

False teachers play down the significance of doctrinal debates and arguments and 'hair-splitting' and so forth, even in the midst of engaging in it, because they know it effects, at practical levels, internal states and status.