If anyone says that Christians should not marry more than one person because it is against the law, I always think of Saint Valentine who (as legend has it) was martyred for marrying Christians when it was against the law to do so, and the double standard of why it would be OK (in the minds of some) to marry a first spouse if it was against the law, but not a second.
If someone says that it is against the law I always ask them, "If it was against the law to marry your first spouse, would you go ahead and marry, or would you refrain with respect to the civil law?"
If someone says that it is against the law I always ask them, "If it was against the law to marry your first spouse, would you go ahead and marry, or would you refrain with respect to the civil law?"