There are two types of slavery.

The first is industrial slavery, in which people are forced to do very hard work, often under the lash, in very difficult situations. Life was usually nasty, brutish, and short. Of course, the easy example is picking cotton in the Old South. It was said that it was better not to be born at all than to be a slave on a large cotton plantation. *

The second is domestic slavery, in which slaves worked very close to the family, sometimes cooking, cleaning, teaching children. These slaves were treated almost like members of the family. In the Roman epoch domestic slaves often had higher social status than poor freedmen. An idea of the life of Roman domestic slaves can be found in Plautus--or in the film (and play) A Funny Thing Happened on the Way to the Forum (based on Plautus).

When Scripture tells slaves to obey their masters, it is not referring to industrial slaves.

And it's not necessarilly a matter of freedom. There have been young men in the US who were drafted into the military out of high school. A year or two later they were in a cemetary in Europe or the Pacific.

* Toward the end of the 18th century slavery was starting to die out. One event, however, not only prolonged but actually increased it. In 1793 the invention of the Cotton Gin caused a huge increase in the demand for cotton, thus an increase in the need for cotton pickers, thus slaves.

Father Martin is using sophomoric arguments regarding the Bible and slavery. For starters, many of the verses in the OT are about what is essentially an indentured servant not a slave.

Additionally, the rest of the verses have subsequent passages that require humane treatment of the 'slave' and also the terms by which the 'slave' can become free.

The Jews have always read the Torah through a rabbinic interpretive lens and not simply on the plain meaning of its words.