Titus of Bostra
Catena Aurea · Lukasevangelium 8
Then came to him his mother and his brethren, and could not come at him for the press. And it was told him by certain which said, Thy mother and thy brethren stand without, desiring to see thee. And he answered and said unto them, My mother and my brethren are these which hear the word of God, and do it.
Our Lord had left His kinsfolk according to the flesh, and was occupied in His Father’s teaching. But when they began to feel His absence, they came unto Him, as it is said, Then came unto him his mother and his brethren. When you hear of our Lord’s brethren you must include also the notions of piety and grace. For no one in regard of His divine nature is the brother of the Saviour, (for He is the Only-begotten,) but He has, by the grace of piety, made us partakers in His flesh and His blood, and He who is by nature God has become our brother.