Lord Chief Justice Sir Declan Morgan was speaking during a court battle over whether humanist marriages should be legally recognised in the region.
The high-profile hearing involving model Laura Lacole and Leeds United and Republic of Ireland footballer Eunan O’Kane temporarily resumed in the Court of Appeal in Belfast on Monday.
The couple originally won a landmark case to have their humanist wedding in June recognised in law.
However, Northern Ireland’s Attorney General John Larkin and Stormont’s Department of Finance challenged the outcome of the High Court decision before the Court of Appeal.
But before legal arguments were reopened Sir Declan told the court that under the Northern Ireland Marriage Order a registrar is under obligation to provide the same equality of opportunity to a secular marriage as to a religious marriage.
“A religious marriage is no better than a secular marriage. A secular marriage is no better than a religious marriage. They are both of legal standing,” he said.
Sir Declan added: “There is a statutory duty on a public authority to promote equality of opportunity.”
He suggested that the appeal proceedings be stayed to allow for consideration of another section of the law.
That issue will be mentioned at a hearing next month. The appeal hearing has been adjourned for mention in November.
In June the Appeal Court judges granted Ms Lacole and Mr O’Kane interim permission to have a legally-binding humanist ceremony.
But the Government of Northern Ireland is attempting to prevent any further legal humanist marriages from taking place.
Humanist marriages are already legally recognised in Scotland, but not in England and Wales. They are also recognised in the Republic of Ireland.
Ms Lacole and Mr O’Kane first launched the legal bid after learning their planned humanist wedding in Ballymena’s luxury Galgorm Resort would not be recognised in law.
For such recognition, they were told, they would need to have a separate civil ceremony.
The couple took the case against the General Register Office for Northern Ireland and Stormont’s Department of Finance.
In the original High Court judgment, Mr Justice Colton quashed the GRO’s refusal to grant legal recognition, finding such a position breached the couple’s rights under the European Convention.
Humanism is a non-religious belief system that rejects the concepts of a higher deity or afterlife.
Humanists adhere to a scientific view of the world and believe humans steer their own destiny.