The Catechism of the Summa - SECOND SECTION - A DETAILED SURVEY OF MAN'S RETURN TO GOD - XXVIII. OF RELIGION AND ITS NATURE

What is the virtue of religion?

The virtue of religion (so-called because it constitutes the bond par excellence which unites man to God, who is the source of all man's good) is a perfection of the will inclining man to acknowledge as it behoves his absolute dependence upon God, who is the first beginning and last end of all (LXXXI. 1-5).
 
What are the acts of religion?

Every act which, of itself, makes man recognize his dependence upon God is the proper object of the virtue of religion. But this virtue also may ordain to this same end all the acts of the other virtues; and in this case it makes the whole of man's life an act of the worship of God (LXXXI. 7, 8).
 
In the latter case what is it called?

It is called sanctity. For the saint is precisely he whose whole life is transformed into an act of religion (LXXXI. 8).
 
Is the virtue of religion most excellent?

Yes, for after the theological virtues it is the most excellent of all the virtues (LXXXI. 6).
 
Whence does the virtue of religion derive this excellence?

It comes from this, that among all the moral virtues whose object is to perfect man in every order of conscious activity in his striving after heaven, such as faith, hope, and charity, there is no other virtue whose object approaches so nigh to this end. The other virtues direct man, either in regard to his own conduct or in regard to other creatures, whilst religion directs him towards God: it effects that he look to God, as it behoves, by recognizing His Sovereign Majesty, serving and honouring Him by his acts as the one whose excellence infinitely surpasses every created thing (LXXXI. 6).

Next - XXIX. OF RELIGION AND ITS INTERIOR ACTS: OF DEVOTION; OF PRAYER, ITS NATURE AND NECESSITY; OF THE "OUR FATHER" OR THE LORD'S PRAYER, AND ITS EFFICACIOUSNESS