[quote="LemonAndLime, post:1, topic:234985"]
I have been given a prayer card as a gift previously, and a card with the 23rd Psalm on it. I use one as the bookmark for my Bible and the other as a bookmark in my devotional book for the Holy Souls in Purgatory (which contains prayers, Chaplets, information).
At Mass yesterday I overheard someone saying they were planning on buying a Mass card.
What are Mass cards/prayer cards meant to be used for? At RCIA we haven't really talked about Catholic devotional objects e.g. scapulars etc even though they're sold at Church, so I really have no idea about these things.
you can ask at your parish, or through societies of missionary priest for a Mass to be celebrated for your intention--most often for a deceased loved one, or for healing, but it can be for any worthy intention. Some parishes or missionaries give you a pretty commemorative card which you can give as a record of your gift to the family or the individual. That is what we mean when we say "I gave or received a Mass card."
Each priest is allowed to accept only one offering (which is modest and voluntary, usually about $5, called a stipend) for each Mass he celebrates. A pastor must celebrate one Mass each week for the people of the Parish. Since he is limited to usually one Mass a day, 3 on Sunday obviously there is a limit to the number of offerings that can be accepted by any one priest or parish. It is common for instance when arranging a CAtholic funeral for the family to ask in advance for a Mass to be said for their loved one on the anniversary of the death or funeral. Most missionary priests however are not scheduled so completely so a donation and request for Mass are accepted by those orders, and the Mass celebrated by any priest available. A priest can offer the Mass for an infinite number of intentions, but can accept only one stipend or donation for each Mass he celebrates.
the logic behind this is covered in the larger topics of intercessory prayer, indulgences, and prayer for the dead that you can research on the apologetics forum.