> Marriage vows are meaningless in a non-religious context.
Since marriage was a legal contract of the government before the Church got involved (originally, at something of arms length) in blessing marriages, and because it remained a legal contract enforceable through the civil courts even after the Church got deeply involved, I don't think that's even a little bit true.
It may be true that various modern concepts like no-fault divorce have made specific legal consequences of violating the express or implied promises in marriage less significant in the modern world, mutual promises have meaning even outside an enforcement regime, and the historical precedent of a non-religious enforcement regime demonstrates that the religious content is not essential to meaning even if you view meaning as requiring an external punishment structure.
Since marriage was a legal contract of the government before the Church got involved (originally, at something of arms length) in blessing marriages, and because it remained a legal contract enforceable through the civil courts even after the Church got deeply involved, I don't think that's even a little bit true.
It may be true that various modern concepts like no-fault divorce have made specific legal consequences of violating the express or implied promises in marriage less significant in the modern world, mutual promises have meaning even outside an enforcement regime, and the historical precedent of a non-religious enforcement regime demonstrates that the religious content is not essential to meaning even if you view meaning as requiring an external punishment structure.