But, the apostle says, if the food is advertised as sacrificed to idols, abstain from it for the sake of the consciences of those around you (1 Cor. 8:7-9).
This is the difference between investigating a doughnut shop owner’s buying habits before eating there and stopping in for doughnuts when the sign out front flashes: “Eat here and support our owner’s cocaine and prostitutes habit.”
You need not investigate as a wedding photographer whether the wedding you are photographing is Christ-honoring. But when there is an obvious deviation from the biblical reality, sacrifice the business for conscience, your own and those of the ones in your orbit who would be confused.
That said, don’t be mean.
The couple asking you to do this wedding aren’t your enemies (Eph. 6:12). They are made in the image of God and are loved by him, and so should be loved by us.
As orthodox Christians, we don’t believe this leads to the happiness they’re looking for, but we must stand with kindness as well as with conviction.
Tell the couple that you wish them well, but that you have beliefs about marriage that won’t allow your conscience to participate in this way. Thank them for asking you, but recommend a photographer who can click away with a clear conscience.