CANON 1
But the sacrament of baptism, which by the invocation of each Person of the Trinity, namely of the Father, Son, and Holy Ghost, is effected in water, duly conferred on children and adults in the form prescribed by the Church by anyone whatsoever, leads to salvation. And should anyone after the reception of baptism have fallen into sin, by true repentance he can always be restored. Not only virgins and those practicing chastity, but also those united in marriage, through the right faith and through works pleasing to God, can merit eternal salvation.
CANON 51
Summary. Clandestine marriages and witness to them by a priest are forbidden. Marriages to be contracted must be published in the churches by the priests so that, if legitimate impediments exist, they may be made known. If doubt exists, let the contemplated marriage be forbidden till the matter is cleared up.
Text. Since the prohibition of the conjugal union in the three last degrees has been revoked, we wish that it be strictly observed in the other degrees. Whence, following in the footsteps of our predecessors, we absolutely forbid clandestine marriages; and we forbid also that a priest presume to witness such. Wherefore, extending to other localities generally the particular custom that prevails in some, we decree that when marriages are to be contracted they must be announced publicly in the churches by the priests during a suitable and fixed time, so that if legitimate impediments exist, they may be made known. Let the priests nevertheless investigate whether any impediments exist. But when there is ground for doubt concerning the contemplated union, let the marriage be expressly forbidden until it is evident from reliable sources what ought to be done in regard to it. But if anyone should presume to contract a clandestine or forbidden marriage of this kind within a prohibited degree, even through ignorance, the children from such a union shall be considered illegitimate, nor shall the ignorance of the parents be pleaded as an extenuating circumstance in their behalf, since they by contracting such marriages appear not as wanting in knowledge but rather as affecting ignorance. In like manner the children shall be considered illegitimate if both parents, knowing that a legitimate impediment exists, presume to contract such a marriage in conspectu ecclesiae (not clandestinely) in disregard of every prohibition. The parochial priest who deliberately neglects to forbid such unions, or any regular priest who presumes to witness them, let them be suspended from office for a period of three years and, if the nature of their offense demands it, let them be punished more severely. On those also who presume to contract such marriages in a lawful degree, a condign punishment is to be imposed. If anyone maliciously presents an impediment for the purpose of frustrating a legitimate marriage, let him not escape ecclesiastical punishment.
Source: https://www.fordham.edu/Halsall/basis/lateran4.asp
Tags: cladestine marriages