If any of us steps back to try to look at the whole of what we call Catholicism today, we should find ourselves dumbstruck by the sheer, absurd immensity of it all. No one can know it all, and yet all of us can be lifted up and brought to greater devotion by every little piece.
Our Tradition is akin to a fractal pattern: a beautifully simple whole, united by the consistent application of a guiding principle, but which offers ever new complexity and detail to the dedicated observer.
[ It’s a funny little coincidence that the teaching of the Church would be a reflection of one of the most persistent and wondrous aspects of Creation, no? ]
Work your way through the whole of the Catechism, read every Papal exhortation and encyclical, compile and pore over the major documents of all 21 Ecumenical Councils… and you still won’t have touched the first volume of St. Aquinas’ great Summa Theologica, the first pages of St. Augustine’s deeply personal and moving Confessions, or first words of the philosophically poetic, yet doctrinally powerful, Quicumque Vult attributed to St. Athanasius—to name only three! …and to say nothing of the great history of prayers and devotions and hagiographies and gestures and sacramentals and so on and so on…
None of us is ever “good enough” to teach catechesis; for however good we are, how could it ever be enough? Nevertheless, we work to be better than we are and trust that, by the grace of God, the Holy Spirit will guide us and make us effective.