The Church's moral teaching role
The Church teaches moral principles to help the baptized live their vocation in Christ. The precepts establish basic responsibilities of worship, sacramental life, penance, and support for the Church. These minimum duties do not exhaust charity. Universal teaching should be distinguished from particular disciplinary rules and local application, especially when comparing Latin and Eastern Catholic practice.
Follow the sources
An original library introduction, with sources for further study. This is a starting point rather than a complete treatment or a finished formation lesson.