"But to make this our reasoning for accepting prostitution is to intimate that sex is only a physical act. I maintain that it is much more than a mere physical transaction. To buy and sell it on the open market dishonors us as human beings made in the image of God."
Well, for you, perhaps, the sexual act is something more than a physical act. That belief, however, is not held by everyone, I'm afraid. And, sex is obtained by many under false pretenses, often taking in people who might believe as you do.
The bottom line is that we, as mammals, have a drive to reproduce. That drive is biological. All mammals have sex in essentially the same way. Only humans have the capacity to raise it to some other level, using their intellect. Still, the mammalian drive remains, and not everyone is willing to rationalize sex into some sort of holy act.
Thus, we have prostitution. We also have casual sex among adults. One is illegal. The other is commonplace.
I disagree with the line of argument you are presenting here. While sex is indeed biological, and a sex urge is included in everyone, that in no way indicates that the state is obligated to allow sex for money transactions in the open marketplace.
I am also instinctively angry when someone treats me unfairly. The state does not allow me to pay someone to beat them to death to fulfill my violent urges.