First, we must recognize that the Bible does not say God supports slavery. In fact, the slavery described in the Old Testament was quite different from the kind of slavery we think of today - in which people are captured and sold as slaves. According to Old Testament law, anyone caught selling another person into slavery was to be executed:"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)
The text you compared (Leviticus 25:44-46 AND Leviticus 19:33-34) are not contradictory.
1. In Leviticus 25:44-46 does not say what Leviticus 19:33-34, just because it doesn't say that doesn't mean it says the opposite. Example, in Leviticus 25:44-46 does NOT mention that it is alright to mistreat your slave. Just because it doesn't say that does not mean it says the opposite of what Leviticus 19:33-34 say.
2. Exodus 21:20-21. This does not mean it was okay to beat there slaves.
At first glance, it would appear as if God is condoning the beating of the slave, but let's read this carefully. First, we see that this verse in no way CONDONES beating a slave. God does not command the Israelites to beat their slaves, and God surely does not want anyone to be harsh or mistreat slaves. That is not what the verse says at all. Here are a few verses so we can sense of how God feels about it:
(Colossians) 4:1 "Masters, provide your slaves with what is right and fair, because you know that you also have a Master in heaven.
(Ephesians 6:8-9) "knowing that whatever good thing each one does, this he will receive back from the Lord, whether slave or free. 9And masters, do the same things to them, and give up threatening, knowing that both their Master and yours is in heaven, and there is no partiality with Him."
The verse nowhere approves of hitting people or abusing them, but rather, the ENTIRE Bible is consistent on how we should treat people. Any skeptic who tries to isolate this verse to "Prove" that God condones beating a slave just reveals their own sheer desperation. The Israelites who had slaves would have known God's holy laws, and they knew better than to mistreat people. (Exodus 22:21)
So, obviously, slavery during Old Testament times was not what we commonly recognize as slavery, such as that practiced in the 17th century Americas, when Africans were captured and forcibly brought to work on plantations. Unlike our modern government welfare programs, there was no safety-net for ancient Middle Easterners who could not provide a living for themselves. In ancient Israel, people who could not provide for themselves or their families sold them into slavery so they would not die of starvation or exposure. In this way, a person would receive food and housing in exchange for labor.
So, although there are rules about slavery in the Bible, those rules exist to protect the slave. Injuring or killing slaves was punishable - up to death of the offending party. (Exodus 21:20) Hebrews were commanded not to make their slave work on the Sabbath (Exodus 23:12) slander a slave (Proverbs 30:10) A Hebrew was not to enslave his fellow countryman, even if he owed him money, but was to have him work as a hired worker, and he was to be released in 7 years or in the year of jubilee (which occurred every 50 years), whichever came first (Leviticus 25:39-43) In fact, the slave owner was encouraged to "pamper his slave" "He who pampers his slave from childhood Will in the end find him to be a son." (Proverbs 29:21)
The idea that God or Christianity encourages or approves of slavery is shown to be false. In fact, anybody who was caught selling another person into slavery was to be executed. However, since voluntary slavery was widely practiced during biblical times, the Bible proscribes laws to protect the lives and health of slaves. Paul, the author of many of the New Testament writings, virtually ordered the Christian Philemon to release his Christian slave from his service to "do what is proper". In addition, numerous verses from the New Testament show that God values slaves as much as any free person and is not partial to anyone's standing before other people. (Galatians 3:28)
RAPE:
Deuteronomy 21:10-14 These passages have nothing to do with rape.
Numbers 31:14-18 This again mentions nowhere about rape
Many people believe that these woman that were captured were supplied so that the priests could abuse them sexually and rape them. But nothing could be further from the truth. In the previous chapter in Deuteronomy 21:10-14, Moses specifically stated what was to be done with female captives. So again, nowhere does is mention God condoning rape. On the contrary, lets see how God feels about rape.
Deuteronomy 22:25-27 States that there is a punishment for those who commit rape.
2 Samuel 13:12-14. Gods people understood that rape was just not right