What is considered correct: Is the minister and wife invited to reception if they are not considered acquaintances of the families. What about the soloist and the organist.

Generally, brides invite the minister and his wife to the reception. Often times, the minister will also say a prayer before the guests begin eating. They can also decline if they would rather not come to the reception. The soloist and organist do not have to be invited, however many people have friends or close acquaintances sing/play organ at their wedding and then it would be courteous to invite them to your reception also. If you do not know them well, you do not need to include them after the ceremony (since you are paying them to perform), but can do so if you like.