There may be more than one "record" of a marriage. A church may have a record, perhaps of the banns as well as the actual marriage. The local government may have a civil record of the marriage, in addition to possibly having a license, bond, or other materials that were a part of the "application to marry" process. Local newspapers may also mention the event.
Pension records and later documents may provide less contemporary information, but may be just as reliable.
Multiple marriage records doesn't mean "multiple marriages." That's a different tip.