Divine and ecclesiastical law
Some norms express divine law and cannot be abolished by a merely human legislator. Others are ecclesiastical determinations made for the common good and may be revised when circumstances, discipline or pastoral judgment change.
Immutable divine constitution and reformable ecclesiastical legislation
Divine law arises from revelation or the natural moral order and binds independently of later codification. Ecclesiastical law is made by competent authority to order the Church's public life. A canon can declare divine law, apply it, or establish a changeable discipline; interpreters must identify which function is present.
No authority can dispense from a divine prohibition or alter the substance of a sacrament. Ecclesiastical impediments, procedural forms and administrative structures can change according to law. Historical comparison of codes is therefore meaningful only after this distinction.
