Shorter Catechism Q. 10. How did God create man? A. God created man male and female, after his own image, in knowledge, righteousness and holiness, with dominion over the creatures.
Commentary: When God created man, that is, human beings, he created them male and female. He created the male, Adam, first, and then the female, Eve. There are, therefore, two and only two distinct sexes and genders. Sex, as considered anatomical and physiological, and gender, as considered the way of being male and female, are inseparable. Maleness and femaleness pertain to the whole person (body and soul). In other words, a person is not male in terms of sex (body/biological) but can be female in terms of gender (soul/mind). God created man, male and female, and not part male and part female.
God made the man and the woman after his own image. The image of God is not found in them, nor is it merely a part of them as if the image is the soul in distinction from the body. Man, male and female, body and soul (or embodied soul) is the image of God.
Man as the image of God involves his knowledge, righteousness and holiness, with dominion over the creatures. Human beings are rational, moral beings that are capable to rule, all which images God.
Being made after the image of God is that which distinguishes human beings from the rest of God’s creatures. It is also the reason God the Son was able to become a human being and thus our savior. Herman Bavinck wrote: “God could not have been able to become man if he had not first made man in his own image.”