I really don't think Mary was 12 years old. Bear in mind that She was going to marry Joseph (his fiancée). So are you trying to imply that Joseph was going to marry a 12-year old girl?
Luke 1:27 To a virgin espoused to a man whose name was Joseph, of the house of David; and the virgin's name [was] Mary
Also know that Mary was a cousin to Elizabeth who also had given birth at the same time in a very old age. So that should give you a clear insight of how old Mary was. Mary was neither a kid nor a teenager. She was a woman who simply abstained from sexual activities unlike many ladies of her time.
Luke 1:36 And, behold, thy cousin Elisabeth, she hath also conceived a son in her old age: and this is the sixth month with her, who was called barren
Yes, as was common practice at that time and in that part of the world:
See above. You can find any source you like, even Christian apologetics ministries will tell you the same thing I have about Mary's age. Why would you expect cousins to necessarily be the same age btw? Giving birth at the same time does not mean they were born at the same time.
Cousins aren't usually of the same age, but there isn't that much gape in their ages. Although it's possibly true, I still find it strange that the cousin of the "12" years old Mary is somewhere around the age of 70. It just doesn't make sense to me.
How do you know?
Nevertheless you will have a hard time finding any source that says Mary wasn't between 12 and 14. Scholars concur that based on what is known of Jewish tradition of that period, girls could be betrothed at 12 but not married until a little older. For Mary to have been betrothed but not properly married to Joseph yet, she would have had to have been in that narrow age range.
When you say it doesn't make sense, Is this what you're feeling?
I'm comfortable mentally, and an open minded Christian. I'm just expressing my opinion on a controversial subject..that's all.
I appreciate that you challenge me. To be agreed with all the time would be terribly boring.