The first reason would be a reaction against what is wrongly seen as monosexual soul-stereotyping. A wholly male soul, whatever maleness means, or a wholly female soul, sounds unreal and oversimplified. But that is not what sexual souls implies. Rather, in every soul there is—to use Jungian terms—anima and animus, femaleness and maleness; just as in the body, one predominates but the other is also present. If the dominant sex of soul is not the same as that of the body, we have a sexual misfit, a candidate for a sex change operation of body or of soul, earthly or Heavenly. Perhaps Heaven supplies such changes just as it supplies all other needed forms of healing. In any case, the resurrection body perfectly expresses its soul, and since souls are innately sexual, that body will perfectly express its soul’s true sexual identity.
Peter Kreeft, Catholic philosopher and apologist