1.. Excellence of this Virtue.
Perfection is founded entirely on the love of God: "Charity is the bond of perfection;" and perfect love of God means the complete union of our will with God's: "The principal effect of love is so to unite the wills of those who love each other as to make them will the same things." It follows then, that the more one unites his will with the divine will, the greater will be his love of God. Mortification, meditation, receiving Holy Communion, acts of fraternal charity are all certainly pleasing to God - but only when they are in accordance with his will. When they do not accord with God's will, he not only finds no pleasure in them, but he even rejects them utterly and punishes them.
To illustrate: - A man has two servants. One works unremittingly all day long - but according to his own devices; the other, conceivably, works less, but he does do what he is told. This latter of course is going to find favor in the eyes of his master; the other will not. Now, in applying this example, we may ask: Why should we perform actions for God's glory if they are not going to be acceptable to him? God does not want sacrifices, the prophet Samuel told King Saul, but he does want obedience to his will: "Doth the Lord desire holocausts and victims, and not rather that the voice of the Lord should be obeyed? For obedience is better than sacrifices; and to hearken, rather than to offer the fat of rams. Because it is like the sin of witchcraft to rebel; and like the crime of idolatry to refuse to obey." The man who follows his own will independently of God's, is guilty of a kind of idolatry. Instead of adoring God's will, he, in a certain sense, adores his own.
The greatest glory we can give to God is to do his will in everything. Our Redeemer came on earth to glorify his heavenly Father and to teach us by his example how to do the same. Saint Paul represents him saying to his eternal Father: "Sacrifice and oblation thou wouldst not: But a body thou hast fitted to me . . . Then said I: Behold I come to do thy will, O God." Thou hast refused the victims offered thee by man; thou dost will that I sacrifice my body to thee. Behold me ready to do thy will.