2 Of this, then, you have now received, have meditated, and having meditated have held, that you should say, “I believe in God the Father Almighty.” God is Almighty, and yet, though Almighty, He cannot die, cannot be deceived, cannot lie; and, as the Apostle says, “cannot deny Himself.” How many things that He cannot do, and yet is Almighty! Yea therefore is Almighty, because He cannot do these things. For if He could die, He were not Almighty; if to lie, if to be deceived, if to do unjustly, were possible for Him, He were not Almighty: because if this were in Him, He should not be worthy to be Almighty.
To our Almighty Father, it is quite impossible to sin. He does whatsoever He will: that is Omnipotence. He does whatsoever He rightly will, whatsoever He justly will: but whatsoever is evil to do, He wills not. There is no resisting one who is Almighty, that He should not do what He will. It was He Who made heaven and earth, the sea, and all that in them is, invisible and visible. Invisible such as are in heaven, thrones, dominions, principalities, powers, archangels, angels: all, if we shall live aright, our fellow citizens.
He made in heaven the things visible; the sun, the moon, the stars. With its terrestrial animals He adorned the earth, filled the air with things that fly, the land with them that walk and creep, the sea with them that swim: all He filled with their own proper creatures. He made also man after His own image and likeness, in the mind: for in that is the image of God. This is the reason why the mind cannot be comprehended even by itself, because in it is the image of God. To this end were we made, that over the other creatures we should bear rule: but through sin in the first man we fell, and are all come into an inheritance of death.
We were brought low, became mortal, were filled with fears, with errors: this by desert of sin: with which desert and guilt is every man born. This is the reason why, as you have seen today, as you know, even little children undergo exsufflation, exorcism; to drive away from them the power of the devil their enemy, which deceived man that it might possess mankind. It is not then the creature of God that in infants undergoes exorcism or exsufflation: but he under whom are all that are born with sin; for he is the first of sinners. And for this cause by reason of one who fell and brought all into death, there was sent One without sin, Who should bring unto life, by delivering them from sin, all that believe in Him.
Source: On the Creed: A Sermon to Catechumens (New Advent)