The act of repeating a message and explaining it in greater depth

The act of repeating a message and explaining it in greater depth is Catechesis.

Explanation:

Catechesis is a clear example of how a message, or simple words are taken and transmitted in a deeper way and with a background meaning.

If we take the example of a bible, what is done in a church is to read or repeat a fragment of it, and then explain its true meaning in a more thorough way.

Thus achieving a deeper message than what is really written.