Luke 8:21

The moral teacher who gives himself an example to others, when about to enjoin upon others, that he who has not left father and mother, is not worthy of the Son of God, first submits Himself to this precept, not that He denies the claims of filial piety, (for it is His own sentence, He that knoweth not his father and mother shall die the death,) but because He knows that He is more bound to obey His Father's mysteries than the feelings of His mother. Nor however are His parents harshly rejected, but the bonds of the mind are shown to be more sacred than those of the body. Therefore in this place He does not disown His mother, (as some heretics say, eagerly catching at His speech,) since she is also acknowledged from the cross; but the law of heavenly ordinances is preferred to earthly affection.

(Hom. 44. in Matt.) Think what it was, when the whole people stood by, and were hanging upon His mouth, (for His teaching had already begun,) to withdraw Him away from them. Our Lord accordingly answers as it were rebuking them, as it follows, And he answered and said unto them, My mother and my brethren are they which hear the word of God, and do it, &c. (Hom. 41. in Matt.) Now He does not say this by way of reproof to His mother, but to greatly assist her, for if He was anxious for others to beget in them a just opinion of Himself, much more was He for His mother. And He had not raised her to such a height if she were always to expect to be honoured by Him as a son, and never to consider Him as her Lord.

They then who hear the word of God and do it, are called the mother of our Lord, because they daily in their actions or words bring Him forth as it were in their inmost hearts; they also are His brethren where they do the will of His Father, Who is in heaven.

And He therefore knowing their hearts gave them this answer, that meanness of birth harms not, but if a man, though of low birth, hear the word of God, He reckons him as His kinsman. Because however hearing only saves no one, but rather condemns, He adds, and doeth it; for it becomes us both to hear and to do. But by the word of God He means His own teaching, for all the words which He Himself spake were from His Father.