Right, so visiting prostitutes was completely legal, therefore fornication was completely legal. Looked down on? Maybe. I'm sure the women were looked down on. But no law against it. Solomon had a plethora of concubines, so it seems to me that men were admired for having sex with lots of women. At the very least, the holiest of men were granted sex with lots of women for their devotion to God, so...
Legal in the view of the absence of casuistic or case law or even apodictic law, no and I will explain below. But since God’s charges against Israel were often metaphorically connected to “prostitution,” the act of relations with a prostitute were not sanctioned by God, only tolerated. The men were also included in the pejorative view and not just the women.
God defined marriage as one man and one woman in which the act of sexual intercourse was becoming one flesh. Adultery was a sin and if a married man had sexual relations with someone other than his first wife, he was guilty of adultery. The law was broken and just because the Israelites didn’t punish the offender as they should have, doesn’t make the act legal.
In the case of the single man, sex with a prostitute was also punishable but was ignored. Who was the prostitute? Was she divorced? Was she a ruined virgin? If she was divorced, the law is still broken because God never intended that divorce would be practiced and if one had relations with such a person, then adultery was still committed but the Israelites declined to treat it as the sin that it was.
If the woman was a ruined virgin, it means that she was raped or consensually involved in the act and the civil act of marriage was not completed. If she was raped, she and the rapist had still become one flesh and if another man had relations with her, then he was an adulterer. The sexual union is the determiner of becoming joined as one flesh and if one joins with another who is one flesh with someone else, the act of adultery is on those who engage in the act. The original plan for man and woman to become one was initiated in the act of sexual intercourse and it was the signifier of becoming one flesh/husband and wife.
Just because the nation of Israel did not determine these specific acts as sins of adultery does not negate the fact that they were adultery. That is why these details are revisited in the NT as God brings mankind closer to the completion of His plan for us. The sin is on Israel for not holding itself to the original standards of sin that God outlined and allowing the sins to grow until she was cast into the era of dispersion.
Solomon was not within God’s plan when he accumulated the concubines and multiple wives and in fact, he was in violation of God’s command cf Deu 17:17. Solomon garnered these wives as a means of acquiring national advantages in the Ancient Near East (ANE). In the ANE it was customary to seal the deal with a lesser king by the greater king (Solomon) marrying the lesser king’s daughter. This was not sanctioned by God and was sin which Solomon would indeed suffer for in his later years. God allowed this polygamy the same way that He allowed divorce but Jesus reminded Israel that it was because of the hardness of man’s heart that He allowed the practice and not because God sanctioned the practice of divorce or polygamy cf Matt 19:8.
Or divorced. They divorced plenty back then. And again, married women need protection from rape too, so most of women in their society was not protected by any law. And since those virgins that were protected had clauses about when they were held responsible too, those aren't laws about rape.
As I have already pointed out, divorce was not God’s plan and it only existed because of man’s hardness of heart. So, any marriage to a divorced woman would be acts of adultery. Christ addresses the problem in Matt 19 as well. The law and intent was always there in the OT laws but man’s determination to be autonomous led him away from God’s intent and Christ brought it back into focus.
Rape: The legal texts show that rape was the equivalent to murder (Deut 22:26) and as seducing a woman physically (Deut 22:25-27) or psychologically (Deut 22:28-29; Exod 22:16) into sexual intercourse. In those same verses, the legal texts value the consent and value of the woman’s voice. In the case of the wife: The act of rape is what is judged and is not viewed as punishable by death because of the object of the crime. It is the crime itself that is abhorrent which means that the husband should treat his wife with the same concern for her value as God’s created being and this is why the NT expands on the idea of the husband treating the wife the same way he treats his own body.
No, I'm wondering why we should believe that Mosaic Law was directly handed down by God if He overlooked rape and child molestation despite all the numerous fine details of much lesser sins.
As demonstrated, finer details are provided in the NT by Christ and the authors of the epistles and it was also determined that these finer details were provided as a reminder that the original intent of the law was ignored. Finer detail is only provided as one violates the original spirit and intent of the law. For example, when Christ taught about loving your neighbor as yourself the next question was “who is my neighbor?” (Luke 10:29). However, rape was not overlooked and even though the laws that we have looked at only name the virgin they would also take into consideration the wife. This is because, since it is the act that is judged, it follows that the same respect is due for the wife’s desire for or against sexual advances.
Child molestation: This would be included in the laws concerning incest (Lev 18:6). Now again, the details of what molestation are and what the details of the act of sexual intercourse are can be seen as synonymous. In other words, the details of the entire act of sexual intercourse would be the same as what a child molester would do to a child while engaged in the act. This would be not necessarily limited to completion of the sexual act, but rather would include any or all parts of the details of the act.
This is of course in keeping with man’s desire to get away with sin by not committing what he would call the act of intercourse. Something like what a famous person claimed that oral sex was not sex or what the definition of “is” is. See the point? We know right from wrong but we seem to think that if we participate in partial sin that we are absolved from the act itself but this is not how God views sin.
Does the NT do a better job of explaining morality and define more things as immoral than the OT did? You bet. But that's just how morality works. It gets refined over time. People do that all the time on their own without a need for religion to tell them to.
The NT reboots the laws of the OT and reminds us of what the original intent was in God’s plan for mankind. Your assumption that the more detail that is in the law is a sign of evolving morality, but it is just the opposite. We make laws more detailed because we are trying to deny our sins by only committing parts of the sin in question. We deny the intent of the law and demand that details be provided so that we can get close to sin but just miss the judgment for going too far. This is why Christ defined adultery as “looking at a woman” with adulteress intent. The heart is the originator of sin and the body is the tool for its completion. In reality, the plethora of laws that accumulate over time define the culture in decline and not an evolutionary ascending culture.