Is it ethical to assume someone's gender based on appearance?

The Bible teaches that humanity is created as male and female (Genesis 1:27), providing a binary foundation for human existence. Historically, human communication relies on using visual cues (appearance, voice, clothing) to make assumptions about a person's sex and gender identity for the sake of social interaction. However, Christian ethics requires that these assumptions be guided by love, respect, and dignity. It is unethical to insist on an assumption or use a person's appearance to deliberately disrespect, mock, or invalidate their self-identification. The Christian response should prioritize showing honor to all people (1 Peter 2:17) while seeking wisdom on how to communicate truthfully and graciously in a complex cultural landscape.