Human sexuality is hotly disputed today, with many now contending that “gender” is a set of learned behaviors that have no intrinsic basis in a person’s sex. The idea is that being born with male body parts doesn’t require a male to obey Paul’s command to “act like men” (1 Cor 16:13), just as being born with female body parts would not require a female to be ladylike (cf., though, 1 Cor 11). Telling a boy not to act like a girl is offensive to those who conform to prevailing opinion in our culture, which would also teach children that “transgender” is normal.
The Bible teaches, however, that God made man male and female, and the Bible clearly stipulates that males and females have gender roles assigned according to sex.
The most basic aspect of this is something our culture is at war against: the way that men are to be fathers and women are to be mothers, God having created male and female such that they have the requisite biological equipment to fulfill these roles.
The very terms used to describe the man and the woman in Genesis 1:27 reflect the way that God made man and woman to correspond to one another, to complement one another. In the language of Genesis 2:18, God made the woman “according to the front of him.”
The anatomical and biological glory of the way male and female complement one another in God’s good creation (Gen 1:31) is reflected in the terms used for male and female in Genesis 1:27. Here’s an embed from Google Books showing the TDOT entry on zachar, the term used for “male” in Genesis 1:27–the relevant portion is in the first full paragraph, beginning with “The etymology,” and be sure to read the third full paragraph as well on the Genesis 1:27 term for “female”:
The language Moses chose to use reinforces what Bible readers have always concluded from these texts: God made man male and female, and he intended them to complement one another. The correspondence between them is built into the biological specifics of what God made and reflected in the linguistic realities of the biblical text.
However the culture might try to redefine sexuality and gender roles, God’s creation is clearly seen, and his word is firmly fixed.