He notes that some of the Jewish religious leaders of Jesus’ time illustrated this problem.
Christ frequently condemned them for following the letter of the law, but not its spirit — that is, its development.
The second note of genuine development is continuity of principles.
Newman insists that for a development to be faithful, it must preserve the principle with which it started.
These Christians recognize — and Catholics acknowledge — that not all the Church’s teachings are explicitly found in Scripture or the preaching of the early Fathers.
Some doctrines were not stated fully and clearly until much later in the life of the Church.
While doctrine may grow and develop, principles are permanent.
Newman identifies the Incarnation as the fundamental truth of the Gospel.
The third note of genuine development is In introducing this criterion, Newman notes that in the physical world living things are characterized by growth, not stagnancy, and that this growth comes about by making use of external things.
For example, as human beings we grow by taking into our bodies external realities such as food, water and air.