Luke 9:59

Or else, his father was borne down with years, and he thought he was doing an honourable act in proposing to pay the kind offices which were due to him, according to Exodus, Honour thy father and thy mother. (Exod. 20:12.) Hence when calling him to the ministry of the Gospel, our Lord said, Follow me, he sought for a time of respite, which should suffice for the support of his decrepit father, saying, Permit me first to go and bury my father, not that he asked to bury his deceased father, for Christ would not have hindered the wish to do this, but he said, Bury, that is, support in old age even till death. But the Lord said to him, Let the dead bury their dead. For there were other attendants also bound by the same tie of relationship, but as I consider dead, because they had not yet believed Christ. Learn from this, that our duty to God is to be preferred to our love for our parents, to whom we show reverence, because through them have we been born. But the God of all, when as yet we were not, brought us into being, our parents were made the ministers of our introduction.

He did not refuse the discipleship, but his wish was, having fulfilled the filial duty of burying his father, to follow Christ more freely.

He compares foxes to heretics, because they are indeed a wily animal, and, ever intent upon fraud, commit their robberies by stealth. They let nothing be safe, nothing be at rest, nothing secure, for they hunt their prey into the very abodes of men. The fox again, an animal full of craft, makes no hole for itself, yet likes to lie always concealed in a hole. So the heretics, who know not how to construct a house for themselves, circumscribe and deceive others. This animal is never tamed, nor is it of use to man. Hence the Apostle, A heretic after the first and second admonition reject. (Tit. 3:10.) But the birds of the air, which are frequently brought in to represent spiritual wickedness, build as it were their nests in the breasts of the wicked, and as long as deceit reigns over the affections, the divine principle has no opportunity to take possession. But when a man has proved his heart to be innocent, upon him Christ leans in some measure the weight of His greatness, for by a more abundant shedding of grace He is planted in the breasts of good men. So then it does not seem reasonable that we should think him faithful and simple, who is rejected by the judgment of the Lord, notwithstanding that he promised the service of unwearied attendance; but our Lord cares not for this kind of service, but only purity of affection, nor is his attendance accepted whose sense of duty is not proved. For the hospitality of faith should be given with circumspection, lest while opening the interior of our house to the unbelieving, through our imprudent credulity we fall a snare to the treachery of others. Therefore that you may be aware that God despises not attendance upon him but deceit, He who rejected the deceitful man chose the innocent. For it follows, And he said unto another, Follow me. But He says this to him, whose father He knew to be dead. Hence it follows, But he said, Lord, suffer me first to go and bury my father.