Catechism of the Catholic Church

18 This catechism is conceived as an organic presentation of the Catholic faith in its entirety. It should be seen therefore as a unified whole. Numerous cross-references in the margin of the text (numbers found at the end of a sentence referring to other paragraphs that deal with the same theme), as well as the analytical index at the end of the volume, allow the reader to view each theme in its relationship with the entirety of the faith.

19 The texts of Sacred Scripture are often not quoted word for word but are merely indicated by a reference (cf.). For a deeper understanding of such passages, the reader should refer to the Scriptural texts themselves. Such Biblical references are a valuable working-tool in catechesis.

20 The use of small print in certain passages indicates observations of an historical or apologetic nature, or supplementary doctrinal explanations.

21 The quotations, also in small print, from patristic, liturgical, magisterial or hagiographical sources, are intended to enrich the doctrinal presentations. These texts have often been chosen with a view to direct catechetical use.

22 At the end of each thematic unit, a series of brief texts in small italics sums up the essentials of that unit's teaching in condensed formulae. These IN BRIEF summaries may suggest to local catechists brief summary formulae that could be memorized.