Does the Bible espouse moral absolutism or moral relativism? I believe that throughout both the Old Testament and the New Testament, the Bible espouses moral absolutism.

Yet, I recently read on this site a response to a question about slavery:


  As stated, slavery was a fact of the Ancient World, and so when the
  Bible addresses the topic, it should not be compared against the
  sensibilities of the modern world, but rather against the
  sensibilities of the ones to whom the Bible was addressed.


...


  It is an anachronism to apply questions of, for example, feminism
  or communism, to the Scriptures, because the original audience would
  have had no means of apprehending it as such.


If this statement is correct, then the Bible cannot appropriately speak to issues like slavery or women's rights because it was written in a different era. Therefore are we all left to interpret and filter the Bible through the lens of our current times and adopt moral relativism for ourselves?



P.S. Here's a quick refresher about the differences between moral relativism and moral absolutism.
I'd like to stand by by statement that it is an anachronism to judge the Scripture from modern biases.
One of the first rules of hermeneutics is that a text cannot mean today what it could not mean to the people who received it. This is a simple enough postulate, buttressed by the fact that not every word of God was for every time, and that the canon we retain consists of that which has proven to speak to all throughout the
ages. But, if it is to speak to us today, it had to have spoken to them then, too.
So, how then can we retain the fact that God is unchanging, and that the moral rules he laid down are transcendent?  We need to remember that God and Man are different.
1. God doesn't change, but people do
First and foremost, God doesn't change, but we do.  Imagine, if you will, one of those cheap holograms that they used to put in kid's cereal boxes.  You could hold the hologram completely still, but depending on your position, it could display two different images.  Even if God is unchanging, very few people would argue that we do. The problems that we face in the 21st Century are different from the problems that we faced in the 1st. Oddly enough, the Bible has nothing to say about the morality of nuclear power! Why? becuase any explanation would have been nonsensical to the original recipients.
The way in which we face our problems also dictates the way in which we will face God. If God were distant, the parallax would make the movement irrelevant. But God is close, and God is involved. As such, he will necessarily appear different, if he has stayed put and we have moved.
In the 1st Century, slavery was a fact of life. As such, it made sense to say, &quot;if you're going to have slaves, treat them well.&quot;  That implied &quot;if&quot; is a very different beast then &quot;you should have slaves.&quot;  In the milennia before Christ, it was permissible to have multiple wives, and so the injunction was given, if you have multiple wives, treat them all well.  That was not a command to marry multiple times by any stretch either. But in an age where silence is now equated with acquiensence, it will appear to us like a tacit endorsement. But to say that is not to make a statement about God, but rather about where we are.
Remember also that laws &amp; principles can remain constant while their interpretation varies.  In 1787, the writers of the Constitution said that Congress should not make any law regarding the establishment of a religion or to prohibit the free exercise thereof.  That had a very specific meaning - In Virginia, the Anglican / Episcopal Church was the established church of Virginia.  The government collected taxes on its behalf, outsourced the institution of marriage, and generally proscribed that all citizens be members of that church.  Nowadays, it doesn't even occur to us to set up a federal church.  And yet, the United States interprets that clause to mean that schools cannot lead prayers, and the City of New York wants to interpret that to mean that churches cannot even pay rent to the school system to use vacant buildings on Sunday mornings. George Mason himself would have been bowled over at such a suggestion. The principle of antiestablishmentarianism itself is  thus absolute, even if its application bears no resemeblance to its former practice.
Finally, the Gospel is not a set of laws any way. It is a message that a gracious God loves us in spite of our sin.  That we are better at following certain laws at certain times and worse in others should be obvious.  Did Christians in the United States sin by holding slaves in the 17th, 18th, and 19th Centuries? Amen, yes, we did.  Did we ignore the principle that before God we are equaly? Amen, God have have mercy.  But I wonder what our great-great-granchildren we think of us.  Did we sin by driving cars like Hummers that were built in total disregard of the command that God gave us to be good stewards of the earth? Its a valid question.  I suspect in the years to come people will be asking how one can be a Christian given our long track record of being such rapacious stewards of the planet we were given to tend.
And yet, I don't think the absolute morality has changed.
2. From God's perspective, we're all sinners anyway. From our perspective, there are only degrees
From God's perspective, we're all sinners anyway. As Isaiah says,

Even our righteousness is as filthy rags.

In God's eyes, we're all sinners anyway. Much of the &quot;law&quot; we have been given is merely to mitigate against the fact, and minimize the harm we do to one another.
The Pharisees asked Jesus if it was ok to divorce a woman.  They knew full well that God &quot;hates divorce&quot; (Malachi) and wanted to trap Jesus.  But Jesus explained the whole purpose of divorce - divorce is totally legal, but not at all desirable.  As Jesus said, divorce was given &quot;because of the hardness of your heart!&quot;  I think we can unequivocally say that God hates slavery, for the reasons in my previous answer.  But he also is willing to meet us where we are.
Our laws, however, recognize that because man is so fallen, there are degrees of punishment that are appropriate. No more than a tooth should be taken for a tooth. No more than an eye may be taken for an eye.  The punishment for a double-homicide is necessarily different from the one for double-parking.  Just because one is not punished for doing a bad thing doesn't make it right. As Jesus said in Matthew 5:45,

&quot;the rain falls on the just and the unjust alike.&quot;

Mere silence on the morality of slavery is not equivelant to support.
The incarnation is such a supreme act of love, because it is a holy God, in whose presence sin can not stand, doing everything He can to reach out to sinners.
Absolutely, He does not change. But relatively speaking, He will do everything He can to be with us, to take us where we are and fit us for where He would have us be.