Did God order “sexual slavery” as you call it? No. There are numerous posts debunking that simplistic reading elsewhere on this site, and is a side-issue of this argument. But essentially, before and after the foundation of the Jewish faith, the Jewish people could be just as mean and hard-hearted as anyone else in the ancient world (or today). They rebelled and ignored the word and law of God throughout the Old Testament, even their greatest leaders. They, like all people in OT times, had people work off their debts as bond-servants, who were not considered property and would eventually be freed. Others, enemy Prisoners of War who had warred against the Jews, were kept as slaves and were expected to work for those who had captured them. This seems harsh to us now (but maybe not, if you look at the modern Prison Industries program) and had a different set of rules, some apparently quite harsh. By comparison to what other peoples may have done (like killing everyone who warred against them), the books of the Jewish law in the OT lay out what would be considered some quite compassionate and lenient rules -
by ancient standards.
As Paul Copan wrote,
Old Testament legislation sought to prevent voluntary debt-servitude. A good deal of Mosaic legislation was given to protect the poor from even temporary indentured service. The poor were given opportunities to glean the edges of fields or pick lingering fruit on trees after their fellow Israelites harvested the land (Lev. 19:9–10; 23:22; Deut. 24:20–21). Also, fellow Israelites were commanded to lend freely to the poor (Deut. 15:7–8), who weren’t to be charged interest (Exod. 22:25; Lev. 25:36–37). And if the poor couldn’t afford high-end sacrificial animals, they could sacrifice smaller, less-expensive ones (Lev. 5:7, 11). Also, debts were to be automatically canceled every seven years. In fact, when debt-servants were released, they were to be generously provided for without a “grudging heart” (Deut. 15:10 NIV). The bottom line: God didn’t want there to be any poverty in Israel (Deut. 15:4). Therefore, servant laws existed to help the poor, not harm them or keep them down.
Copan, Paul (2011-01-01). Is God a Moral Monster?: Making Sense of the Old Testament God (Kindle Locations 2617-2624). Baker Publishing Group. Kindle Edition.
If a person was forced into debt bondage by circumstances, they were granted rights by divine decree that protected them. They could not be physically abused, and had to be released if injured by their master. If they were killed by a master, the master was to be put to death (quite different from the Roman Law and the Code of Hammurabi, under which a slave owner could generally rape, beat, maim or kill slaves with impunity.). They were considered as persons, not property (Gen. 1:26–27; Job 31:13–15; Deut. 15:1–18), and retained their human dignity.
Slave-trading - kidnapping a person against their will to keep or sell as a slave, was forbidden under penalty of death: “He who kidnaps a man, whether he sells him or he is found in his possession, shall surely be put to death.” (Exodus 21:16). St. Paul and St. John also later condemned slave traders in no uncertain terms. (As did St. Patrick and St. Augustine.)
The Israelites were required by Mosaic Law to help and shelter foreign runaway slaves (Deut. 23:15-16) - unlike other ancient cultures, or the American example, where it was a felony to help a fugitive slave.
It was not a perfect or a perfectly just system (no institution run by humans probably can be), and there were obvious inequities by modern standards, but it was superior to any other system of its time, and certainly to the American experience of chattel slavery.
Jesus said such practices, as the old Mosaic laws on divorce, were against what God wanted for His people, but were permitted in olden times because His people’s hearts were hardened, before establishing a new law. Jesus denounced slavery as practiced under the Roman Empire, as he did every form of oppression: Citing Isaiah 61:1, Jesus clearly said His mission was “to proclaim release to the captives, . . . to set free those who are oppressed” (Luke 4:18).
A prevailing theme throughout the Bible (and as cited by Jesus) was that men’s hearts were hard and resistant to God - so to mitigate the damage done, they were gradually led to a greater and more compassionate way to treat people. God did not want his people to have kings, but they insisted on having kings, so God placed limits on their powers. God did not want them to divorce, but since they insisted on doing so, rules were imposed to at least make it more equitable. God did not want them to commit adultery by having sex with captured female slaves, but since they did so, they were given rules to at least treat them with some modicum of decency - again, for the times. It is rather like saying we don’t think anyone should have to work in an asbestos mine, but since people do, here are some OSHA regulations to minimize the damage. Throughout the OT and into the NT, God is trying to keep His people on the straight and narrow, and being people, they continually fall short.
As this concerns the Jewish laws (Jews were more likely to be slaves than slaveholders by the time of Jesus), if you’d like to read a Jewish perspective on this, go to:
chabad.org/library/article_cdo/aid/305549/jewish/Torah-Slavery-and-the-Jews.htm