In my study, I found that this verse was not a command to be the husband of one wife, any more than it was a command that they HAD to have children. (since the verse also says they must be able to rule their children well). But is more a limitation… ie. if they are married, they should be the husband of no more than one wife. Even today, polygamy is acceptable and normal in the middle eastern culture. If we take this as meaning that the person must have a wife to be qualified to be a priest, it would also mean that he could not be a priest if his wife died, because he would no longer be the husband of one wife. In addition, you would have to take this even further and apply it to the other part of the verse that says he must be able to rule his Children well… what happens when they grow up and cease living under his “rule”?
IMO, this verse is a encouragement for an elder to be temperate in his life choices, dealings with people particularly his family. Further if we look at the example of the Apostles lives it is clear that they did not see having a wife or children as a requirement for serving God in Church offices, therefore I think it can be assumed that they believed, even when writing this passage, that it meant that elder/priest had to be married.
Finally, yes the Bible did assume that some would be living married… and some are. It is not the norm in the Latin Rite Church (ie. Roman Catholic), however, it does happen. In addition, it is not uncommon, and is perfectly acceptable for Eastern Rite Churches to have married priests. The Roman Catholic Church completely recognizes these priests as valid priests.
It is not a church “doctrine” that priests cannot marry in the Roman Catholic church… it is a discipline… ie… it is something that the church sees as desirable in it’s priests, but is not actually a doctrine, therefore could change in the future if the Church decided it would be better.
At least that is my understanding…