The Codex is what holds the rest up. The Bible is the foundation; the creeds are the church's anchoring confessions through history; the catechism is the structured instruction. Every Shepherd answer cites these. Every curriculum lesson references these. Every reading plan walks through them.
This page is the navigable index. Click any book, creed, or Q&A to drill in.
24 of the 107 Q&As are surfaced here — the most catechetically load-bearing across God, sin, Christ, salvation, sanctification, the moral law, and the Lord's Prayer. The full 107 are public domain and can be added by an operator pass.