The ability to reliably distinguish between male and female is critical for healthy community; we’re to treat older men like fathers and younger men as brothers (1Ti 5:1), and women distinctly differently as mothers and sisters (2), so gender should be evident by appearance.
To ensure this, God tells women not to wear clothing which pertains to men, and men not to wear women’s clothing (De 22:5a); this requires us to design gender-specific clothing to help us easily determine gender. As we resist this principle we’re an abomination to God (b), so it’s evidently quite important to get gender-distinction right.
In light of this, how do we relate with men claiming to be women, and women claiming to be men? Acknowledging that God makes us male and female, and that He makes no mistakes, is a good place to begin. (Ge 5:2) Sharing this understanding with those who are interested is certainly also appropriate. (1Pe 3:15) But is it consistent with the law of love to refer to a woman as he, or to a man as she? (Ro 13:10)
We must be very careful here: our speech should always reflect the nature of God in us (Co 4:6); we ought to say what we mean and mean what we say (Ja 5:12), speaking always in His name (Col 3:17), walking in His steps (1Pe 2:21), doing what He is doing as He lives in us. (Ga 2:20) We shouldn’t compromise in fear (Pr 29:25), nor align our walk with ungodliness (Ep 4:17), but always speak the truth in love. (Ep 4:15)
This doesn’t mean we say whatever we think to everyone we know, without any filter or consideration; not only is this impossible, it’s generally unloving and unwise. We shouldn’t correct those who’re unreceptive (Pr 9:8): give that which is holy only to seekers. (Mt 7:6) We should carefully weigh our words (Ps 39:1), and be more prone to listen than to preach. (Ja 1:19)
Yet when it comes to choosing our words we must own them, and be very deliberate and precise. (Mt 12:36) Using a word pertaining to a female to refer to a male is to expressly violate this basic principle of gender-distinction, akin to providing him a dress, heels, lipstick and jewelry, and helping him put it all on. It is explicitly conforming our behavior to support and encourage perversion, a mindset diametrically opposed to God’s design.
It is inconsistent with the law of love to encourage or enable a person in their own deception, comforting them in a lie they insist on believing. Every man and woman is so by God’s design, a design that’s perfect and good. To actively align our speech with a rejection of this design is to violate the dignity God has bestowed on us, which cannot be consistent with love. To be a friend of the world by conforming ourselves to it’s rebellion to avoid upsetting or offending with the truth is to be an enemy of God, if anything at all is. (Ja 4:4)
Looking for a gender-neutral way* to communicate is perhaps one way to avoid direct conflict; failing to express an opposing view via a neutral expression seems better than actually aligning with perversion. Yet, even this might be viewed as a compromise: when perversion cannot actually be entirely ignored and must be addressed in some way, would Jesus confront it or modify His behavior to accommodate it?