So I pulled out my catechism — that is, the Catechism of the Catholic Church — for a definition. There isn’t a single definition as in a glossary. But the key items are unity, that is, the two becoming “one flesh” with mutual self-giving; indissolubility; and openness to fertility. To contract a marriage also requires free consent. My understanding — though it’s not spelled out — is that if one of the two never really was open to children or... Read more