@Dev I think there are two lines of thought that help in response to this argument:
I think we can start by acknowledging that the New Testament says the law was not perfect. The law permitted divorce because of the hardness of men’s hearts (Matt 19:8) and not because it was the ideal. The law was a tutor - a temporary reality to foreshadow Christ.
John 1:17 - For the law was given through Moses; grace and truth came through Jesus Christ.
God is actually more of a realist than we are - He met people where they were at culturally rather than trying to force the ideal on them when He knew they could not keep it. Like any wise leader, God was steering the Israelites and the world in a direction which would allow Christ to be understood. God was preparing the world for Jesus. God was preparing the way for the ideal with something temporary that was non-ideal.
Line 1 - This Argument is Rooted in Modern Western Culture
We in the West value autonomy above all else - the freedom to choose as we wish. In ancient culture marriage was at times arranged and your role in society was more important than freedom to choose. So the fact that a woman did not necessarily get to choose who to marry would not be seen as rape. The cultural context was different.
God was working in a particular culture to redeem those within it, so God did not make a mistake or lack knowledge of our modern views. God knew full well that a modern person might be offended by ancient culture. Even today people from one culture must be careful not to offend people from another culture. Ignorance of ancient culture is not a shortcoming on God’s part, but a lack of willingness to study and understand how God was working in that time and place on the part of the critic.
God is the ultimate missionary. When he spoke to a middle eastern people from two thousand years ago he used ideas and language familiar to them to reach them. That is why we modern Westerners have to study that cultural context before judging how God chose to work within that culture.
Line 2 - God Was Working Within Ancient Culture
Here are some thoughts on how God may have been working within ancient culture:
- God was moving the existing culture in a redemptive direction - what we see is not the ideal but movement towards the ideal
- an ancient Israelite would not have understood this as rape. There were other cultures that literally raped women they took captive without their consent and without marrying them. In this case, the women were given 1 month to mourn and then the men had the option to marry them. Marriage is not the same thing as rape
- this arrangement would have been beneficial to the woman, who needed protection
Dt 21:10-11: Were female slaves raped?
The law explicitly condemned all of the following:
Therefore any forced intercourse would have been against both the letter and the spirit of the law.