Homosexuality is unnatural and "against the will of God", the Church said, besides issuing guidelines for women to dress "decently" while attending wedding celebrations.
The policy statement, drafted and issued by the Synod Executive Committee (SEC), said sexual relations should also be only between married couples and that extra-marital affairs were sinful.
"Homosexuality is against the will of God, as God meant only man and woman to have sexual relations and that too only those who entered holy matrimony," the statement added.
Meanwhile, the women's wing of the Presbyterian church also issued guidelines on how to dress "decently" for wedding celebrations in the church, the vestry and wedding receptions in halls.
While discouraging women from wearing "revealing" dresses, the women's wing urged people to dress according to the tradition and customs of the Mizos. "Mizoram is a nation, so we should encourage our national and traditional dress," the directive said.
Bridal gowns should also be made to suit the height of the bride, the statement said, adding that those who attended the wedding in the church should dress "decently".
Frowning upon the trend of relatives of the bride and the groom wearing the same colour, the women's wing said the practice could be embarrassing for other people who attended the wedding service and make them feel uncomfortable.
H Lalpianthangi, assistant coordinator of the women's wing of the Mizoram Synod, said the guidelines would be read out in all local churches. However, as they were just guidelines, no one could be forced to follow them, she added.