It is true the Tanakh (Old Testament) talks of it, but there is no reason to do it anymore, and that God had to cater to the people of the time.
There are about 27 million slaves worldwide, and “he” promised they will be free someday.
Also, it is wrong to oppress women, and if you marry one, she shall your be equal for all eternity.
And treat your pets well, and your animals on the pastures properly.
God freed the people from Egypt, too. And, that says something about the issue. So, who cares about pro-slavery dogma.