Marriage and Divorce
Mark provides a series of parables in chronological order matched to the overall story of the Bible. The parable about Marriage and Divorse is about Moses.
1Jesus then left that place and went into the region of Judea and across the Jordan. Again crowds of people came to him, and as was his custom, he taught them.
2Some Pharisees came and tested him by asking, "Is it lawful for a man to divorce his wife?"
3"What did Moses command you?" he replied.
4They said, "Moses permitted a man to write a certificate of divorce and send her away."
5"It was because your hearts were hard that Moses wrote you this law," Jesus replied. 6"But at the beginning of creation God `made them male and female.' 7`For this reason a man will leave his father and mother and be united to his wife, 8and the two will become one flesh.' So they are no longer two, but one. 9Therefore what God has joined together, let man not separate."
10When they were in the house again, the disciples asked Jesus about this. 11He answered, "Anyone who divorces his wife and marries another woman commits adultery against her. 12And if she divorces her husband and marries another man, she commits adultery." Mark 10:1-12 NIV
1And he arose from thence, and cometh into the coasts of Judæa by the farther side of Jordan: and the people resort unto him again; and, as he was wont, he taught them again.
2¶And the Pharisees came to him, and asked him, Is it lawful for a man to put away his wife? tempting him. 3And he answered and said unto them, What did Moses command you? 4And they said, Moses suffered to write a bill of divorcement, and to put her away. 5And Jesus answered and said unto them, For the hardness of your heart he wrote you this precept. 6But from the beginning of the creation God made them male and female. 7For this cause shall a man leave his father and mother, and cleave to his wife; 8And they twain shall be one flesh: so then they are no more twain, but one flesh. 9What therefore God hath joined together, let not man put asunder. 10And in the house his disciples asked him again of the same matter. 11And he saith unto them, Whosoever shall put away his wife, and marry another, committeth adultery against her. 12And if a woman shall put away her husband, and be married to another, she committeth adultery. Mark 10:1-12 KJV
The parable begins with a crossing of the Jordan river. It takes place on the other side of the Jordan. This is a hint as to the prophetic application of this passage... near the Jordan.
There is a large crowd gathered together in one place, as the ancient Israelites were for the 40 years between leaving Egypt and crossing the Jordan into Canaan.
The Pharisees approach Jesus and ask Jesus if it is lawful to divorce. The entire book of Deutoronomy, one account of the Mosaic law, was given on a single day in the few days before crossing the Jordan.
Jesus pushes back at these men who should be experts in the Law of Moses. He asks what the Law of Moses says about divorce. This, too, is a reference to the time of Moses, setting the general timing of the parable about the year 9040 AA, the last year of the wandering in the wilderness when the Israelites were across the Jordan.
Jesus continues and explains that at the beginning it was not God’s intension that men and women should separate in divorce. At a marriage men and women become one flesh. He concludes with the point of the parable. What God has joined together, men should not separate.
Though this discussion is covering the topic of marriage, the discussion is a parable. In the New Testament marriage is used as a metaphor describing the relationship God has with his people. Paul explains this in a letter where he goes into more depth and states in clear text this is a description of the relationship between people and God. 
Notes on Symbolism
This symbolism is typical of a modern marriage ceremony where the bride and groom walk the isle between the parted community. It is also typical of the Biblical form for covenant making. In order to make a covenant typically an animal, sometimes several animals are cut into two pieces and the parties making the covenant pass between the pieces. The symbolic significance to this ceremony is that if either party breaks their part of the bargain then the offended party has the right to cut the offender into pieces like the animal.
In the case of the Red Sea the the significance is in the meaning of the seas themselves. Seas represent the peoples of the world. (cite from Rev.) By passing through the seas together the Lord and the people make a covenant. Should either break that covenant the offending party will be cut into two pieces and thrown back into the peoples.
Of course the Lord is without sin and will not break his part to a covenant. This is in part why he guards his words so carefully.
The people, though, were the ones prone to breaking covenant. After crossing the Red Sea the people demonstrated that they were quick to break the marriage covenant. The Lord, though, was slow to exercise his part of the covenant. The kingdom itself was not split into two kingdoms until after the reign of King Solomon. There, during the time of Rehoboam king of Judah and Jeroboam, king of Israel, the kingdom was split into two parts. A split that continues to this day. (Between Russia and the English speaking world.)
The adultery that Jesus refers to at the end of this parable is the behavior of the people after crossing the Red Sea. They went after other gods and so broke the marriage covenant they had entered into at the Red Sea. The reason no one would approach Jesus in this matter after his discourse is because no one would approach the Lord early in the time of wandering in the wilderness. Only Moses, here pictured by the disciples, could safely approach the Lord.
In the case of the ancient Israelites leaving Egypt, it was the younger generation, those people in their 19th year or younger at the time of the Exodus, who would be able to cross the Jordan river and enter into Canaan. Those children are the subject of the next parable.
How Often Forgive?
The Matthew version of this Grand Tour picks off a different aspect at this time in history.
21¶Then came Peter to him, and said, Lord, how oft shall my brother sin against me, and I forgive him? till seven times? 22Jesus saith unto him, I say not unto thee, Until seven times: but, Until seventy times seven. Matthew 18:21-22 KJV
21Then Peter came to Jesus and asked, "Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?"
22Jesus answered, "I tell you, not seven times, but seventy-seven times. Matthew 18:21-22 NIV
1. Ephesians 5:22-33