Things that were different that I currently know if.
1.) Jesus was primarily speaking to Jews and was responding to question from Jews when it came to marriage.. Jews who were still bound to the Old Covenant at the time. Are Christians bound to the same covenant?
The Jesus I see is one who would have clearly rejected the Gentiles. He clearly indicated his mission was only to "the House of Israel." He mocked the Gentiles and called them "dogs." I see it as up to the individual believer as to whether to decide their relationship with the "Old Covenant."
Most of Jesus' unique teachings are found in the Hebrew Bible and were a necessary part of Judean tradition and history.
2.) Paul and the Apostles were speaking to Christians and taught very differently about marriage.. who takes precedence if we say all scripture is equally inspired?
This depends on how one reads Paul, since his cultural pronouncements are contradictory. I think this has to do with ignoring his actual letters where the radical Paul holds forth and by preferencing those letters which are forgeries.
3.) Women could not initiate divorce at all back then.
I am not sure this is true. It seems to me that I remembered a different history as Elaine Pagels has documented, but I could be wrong. One thing that sticks in my mind would be that it was always the man who could initiate a divorce, simply because the Christian notion is that patriarchy is mandated from God.
4.) Men did not always divorce their wives.. there was the custom of putting away a wife which was pretty fraudulent.
That's interesting; I have never heard that before.
5.) Men had multiple wives back then. It was common among first century Christians too.. hence we have the restriction on elders only having one wife.
