There is no set age that is appropriate for marriage. Much of the discussion comes down to the maturity of the two people who are considering marriage as well as what is acceptable culturally.
Genesis tells us that Isaac was 40 years old when his father Abraham sent his servant in search of a wife for him. Rebekah was likely much younger than this when she married Isaac.
No ages are ever given for Mary and Joseph but many biblical scholars believe that Mary was young, most likely a teenager when she gave birth to Jesus.
Young teenagers are physically able to have children and start a family at the time of puberty. This does not mean that they are mentally or emotionally ready for marriage. When life spans were only 35-40 years people married younger out of necessity. They did not have the luxury of waiting until their late 20’s or 30’s to begin having children if they wished to see them grow into adults.
Still today, women have a short time when they are capable of having children and if a woman wants children, this will certainly influence when they get married. Guys do not have such an issue and this may be one reason why they typically are not interested in settling down until later than women.
There are other factors that influence when a person should get married that have nothing to do with the Bible. First of all is the legal issue. In many places a person can’t get married without parental permission until they are 19 years old.
Education is another factor to consider when getting married. In earlier times when most women were content to be stay at home moms, education wasn’t a priority. Today many women are going to college and pursuing careers. This is a matter of choice and is neither good nor bad. Each person needs to decide what their priority is.
Still another factor that must be considered before getting married is financial stability. In a traditional marriage, the man was older and more established and therefore able to take care of his wife before he got married. There were also far fewer things that required money. Not long ago a person was expected to provide a home and food for the family. Anything leftover after this was a bonus.
Today in addition to the basic needs of life, there are several more bills for things that most people can no longer live without. Cell phones, cable tv, and high speed internet quickly cost a couple hundred dollars a month. This is in addition to paying off high student loans that many people did not have to deal with a generation ago.
In short, there is no acceptable time to get married aside from once it is legal to do so. The right time will depend greatly upon the couple and their goals in life. Marriage is a major commitment and should not be rushed into. Only after much prayer and consideration should a couple think about marriage, regardless of their age.