Yes, in reading these verses there is a clear theme that there is limits to the ownership of slaves. However, selling yourself or being sold into servitude through a civil judgment (both condoned in these verses) is still a bit questionable. Today a contract can be broken and sorted out in the courts if there is a question of the legitimacy of the agreement and there is no beating someone because they are not fulfilling their end of the bargain to your satisfaction.

So, I can appreciate the protections given to slaves here. However, it is a real problem for the credibility of a book that claims to be a TIMELESS moral compass.