Addendum on Resisting Redefinition
I've been thinking a little more on the need to guard against the casual adoption of the language of the PC establishment.
What I have found really helpful in thinking about this question is some recent reading about Martin Luther's 'Theology of the Word'. The German Reformer, pointing to biblical texts like Genesis 1.3, Romans 10.17 or 2 Corinthians 4.6, believed that the Word of God, as Carl Truman summarizes, "not only describes reality but also determines reality: all reality," in 'Luther and the Christian Life' (p.80).
From the point of view of the Gospel, it is good to ask the question, why is it necessary and important to resist redefinition? Can I suggest that it would be good to bear in mind some or all of the following reasons?
First, because the chief instrument Satan uses to promote unbelief and undermine the truth, is the lies he tells. One example might be the lie of 'same-sex marriage.' In reality there is no such thing. Marriage is between one man and one woman. This linguistic redefinition is a false construction of the PC establishment which bears no relation to reality before God.
Second, because this blinding power of words is only removed by the truth, applied in the power of the Spirit, and received by faith. If we work the above example out, this false construct is removed from people's mind, by the light and power of the Spirit, when they receive the truth by faith: we correct the error with the Word of God which says that the Creator ordained marriage to be a one-flesh, monogamous, male-female, loving bond.
Third, because the power to blind is weakness in comparison to the mighty Word of God - the Gospel is saving power, the Word God's chosen means of grace, that constitutes and recreates spiritual reality in the lives of dead sinners. This means that when the Word comes to the People of God with power, they eventually see the error of the academic elite, and refuse to adopt this falsehood.
If that is the case, we would be mistaken to just dismiss the post-modern conviction that words create new realities (a contemporary version of Ockhamist Nominalism, for those who are interested), as mere empty talk and barely worthy of our notice, even if we believe and know that mere, human, words lack any true potency in the realm of reality.
Mere human words have no power to create true realities - we must be clear on that!
Human words do, however, have the tempting, confusing, blinding, deluding, power to spawn or engender false imaginary ideas, illusions or unbelief in the minds of those who hear them. Lies of the world, flesh and devil, certainly have the power to build foundation-less tenements of societies constructed on the sands and over to-be-finally-glaringly-exposed, sink-holes of myth. It is for that reason, the new PC vocabularies and glossaries, are ignored by believers, at the peril of truth.
Equally, of course, Gospel words will miraculously and mightily dispel these lies and myths - we don't need to panic that such errors and showers of lying words will finally prevail - they can't and won't thwart the progress of the church of Christ in any ultimate sense: we do, however, need to keep our heads: where the lies are believed or remain unchallenged, many will turn from the truth, and be confirmed in their sinful prejudices and enslaved practices.
Ultimately, the only way of pulling down these flimsy cardboard constructs erected by the elite is by preaching the truth, correcting the errors, and by inculcating into minds the proper biblical vocabulary, and rock-solid theology that truth raises up. God's true words give life to the dead and conform saints to the image of His Son. That is why I contend we must be should be much more terminologically cautious than is current. As Truman observes: