If the Catholic spouse obtains the bishop's permission to marry in a non-Catholic ceremony and both spouses are free to marry, then anybody may attend the wedding. However, if the ceremony includes a communion service, Catholics may not accept communion in a non-Catholic wedding. In this case, either the Catholic spouse must find another church willing to bless their union without receiving any communion or they should wait until after their first anniversary to be married in order to receive communion at their wedding.
In general, Catholics are encouraged to find a priest in their diocese who will perform marriages according to the rites of their parish so that they can receive the Eucharist during the marriage ceremony. If this is not possible, then their marriage would not be considered valid before God and would not confer any rights on the couple.
However, there are cases where Catholics may need to get married outside of their local area in order to obtain the blessing of a priest who will perform their wedding ceremony according to the rules of Catholicism. For example, if one or both spouses are living in an area where there is no priest who will marry them according to Church law, then they would have to go to such places as India, Malaysia, or Thailand where these marriages are legally binding.
All Catholics are welcome to attend, but reservations are required. It satisfies both natural and canon law. On rare occasions, a practicing Catholic will fall in love with a non-Catholic and seek to marry in a non-Catholic church, for example, because the spouse's father is the minister of the local Protestant congregation. In this case, the couple would need to obtain a declaration of nullity from their priest to prove that they were truly married by valid rites.
The Catholic Church does not consider ecumenical marriages to be valid marriages, but only gives its blessing to such unions. For example, if a Catholic married an Orthodox Christian, they would be permitted to return to their pastor to receive absolution and communion before going on a honeymoon if they so chose. However, there are no Orthodox churches in America who perform marriages, so this option would not be available to couples who get married outside of their community.
Catholics who are divorced and remarried without an annulment are barred from receiving Eucharist at Mass unless they submit to a declaration of sinlessness from their bishop. However, it is possible that a divorced and remarried person could concelebrate Mass with a priest if they have made a good faith effort to resolve their marriage conflict and neither party refuses reconciliation.
Both parties do not need to be Catholic to be sacramentally married in the Catholic Church, but they must both be baptized Christians (and at least one must be a Catholic). A Catholic must obtain formal approval from his or her bishop before marrying a non-Catholic Christian. If one party is not Catholic, there are forms that the non-Catholic party can fill out to become Catholic for the purpose of being married.
Generally speaking, anyone who has been baptized into the Catholic Church is called to marry another person in a Catholic ceremony. However, those who have received instruction from their bishops on how to conduct themselves as Catholics who are not of the same parish may be granted an exemption from this requirement. Such couples would be permitted to receive Holy Communion together but could not remarry after divorcing civilly unless they convert to Catholicism or else are reconciled with its teachings by their local bishop.
However, if a Catholic wants to marry someone who has never been baptized or who has been baptized but not yet confirmed as a Catholic, he or she will need to go through a process known as "catechumenation" to learn more about the faith and be prepared to make a commitment to live it out daily life. This could include living in monasteries for some time so that you can learn how to manage money wisely and prayerfully.
If the Catholic has a civil wedding ceremony with the petitioner, the petitioner is still married to someone else, implying that the Catholic is engaging in adultery with someone else's spouse. Because this is a grave deadly sin, the Catholic would be unable to take communion while living in this scenario. However, if the Catholic receives communion during a period of grace when he is not aware of his marriage, then this would not be a mortal sin.
However, if for some reason the Catholic feels she cannot receive communion without first receiving a blessing from a priest, she could ask that it be given post-facto. The Catholic Church allows for priests to give blessings after the fact if necessary. This is usually done for situations where there is no other way to receive holy communion or if the person does not have access to a priest but would like to receive it nonetheless.
In addition, if a Catholic is divorced and remarries without an annulment, they are still married and can't receive communion until they are able to receive it again. If they die without being able to receive communion, they will not enter heaven because they were still married at the time of their death.
Finally, if a Catholic ever abandons her faith and stops going to church, she would be automatically excommunicated and would not be allowed to enter heaven even if she was never told about any of these rules.
If your wedding is to be held in a non-Catholic church, the Catholic spouse must also get a "dispensation from canonical form" (i.e., a waiver of the formal requirements that the wedding occur in a Catholic church and the use of the ordinary marriage rite, witnessed by a Catholic priest). This can be done by having a license from a civil authority as well as an endorsement from one's local bishop. In some cases, especially if the church does not want to grant such a dispensation, it may be possible for the couple to wed privately without any witnesses other than their pastor and perhaps a close family member or friend.
In most cases, however, Catholics are expected to marry only in a Catholic church with a Catholic priest present. The wedding ceremony itself is considered sacred and cannot be replaced by a secular official or group.
The need for a Catholic marriage has always been emphasized by the Church. The Catechism of the Catholic Church states: "Christian marriages are ordained by God Himself through Christ His Son, in order to preserve humanity from death and destruction. They should therefore take place before priests in the presence of at least one other person who supports and assists the husband and wife during this important time in their lives."
Although it is possible to get a marriage license and have a non-Catholic perform the service, this violates fundamental Catholic beliefs and practices.