Fourth degree: third cousins, who share the same great, great grandparents
Therefore, if second cousins wished to marry one another, they would need to be granted a dispensation for a third (or third to third - 3/3) degree of consanguinity from the Church before the marriage could be solemnized.
Among the Acadians of southeastern New Brunswick, dispensations were not always that simple. A couple could be third cousins through their mothers, as well as their fathers, requiring a dispensation for a double, fourth degree of consanguinity. A relationship could also be uneven where as the groom's grandfather was the brother of the bride's great grandfather requiring a dispensation for a third to fourth degree of consanguinity, because they were second cousins, once removed.
Dispensations were not limited to blood relationships. There were also spiritual relationships. When a person married, that person became a spiritual member of the new spouse's family. A sister-in-law was, in a spiritual sense, a sister. This applied to brothers, cousins, etc. If a man wished to marry his late wife's first cousin, spiritually he would be marrying his own first cousin. This would require a dispensation for a second degree of affinity. Dispensations for affinity relationships were governed by the same guidelines as blood relationships of consanguinity.
Dispensation play a major role in New Brunswick-Acadian genealogy. With a lack of surviving, original records of the late eighteenth-century and a number of nineteenth-century marriage records in which the parents of the couple were not noted, dispensations are a valuable tool in the confirmation of ancestry and relationships. Dispensations are used by professional researchers in determining if indeed such and such ancestors were related to one another because of the dispensations being granted their children, etc.