Ante-Nicene Fathers, Vol IX:
Origen's Commentary on the Gospel of Matthew.: Chapter XVI

16.  Why the Great are Compared to Little Children.

But first we may expound it in simple fashion.  One, expounding the word of the Saviour here after the simple method, might say that, if any one who is a man mortifies the lusts of manhood, putting to death by the spirit the deeds of the body, and “always bearing about in the body the putting to death of Jesus,” 5927 to such a degree that he has the condition of the little child who has not tasted sensual pleasures, and has had no conception of the impulses of manhood, then such an one is converted, and has become as the little children.  And the greater the advance he has made towards the condition of the little children in regard to such emotions, by so much the more as compared with those who are in training and have not advanced to so great a height of self-control, is he the greatest in the kingdom of heaven.  But that which has been said about little children in respect of lustful pleasures, the same might also be said in regard to the rest of the affections and infirmities and sicknesses of the soul, into which it is not the nature of little children to fall, who have not yet fully attained to the possession of reason; as, for example, that, if any one be converted, and, though a man, such an one becomes as a child in respect of anger; and, as is the child in relation to grief, so that sometimes he laughs and plays at the very time that his father or mother or brother is dead, he who is converted would become such an one as little children; and, having received from the Word a disposition incapable of grief, so that he becomes like the little child in regard to grief.  And the like you will say about what is called pleasure, in regard to which the wicked are irrationally lifted up, from which little children do not suffer, nor such as have been converted and become as little children.  As, then, it has been accurately demonstrated also by others, that no passion is incident to the little children who have not yet attained to full possession of reason; and if no passion, clearly fear also; but, if there be anything corresponding to the passions, these are faint, and very quickly suppressed, and healed in the case of little children, so that he is worthy of love, who, being converted as the little children, has reached such a point as to have, as it were, his passions in subjection like the little children.  And with regard to fear, therefore, similar things to those spoken might be conceived, that the little children do not experience the fear of the wicked, but a different thing, to which those who have an accurate knowledge of questions in regard to the passions and their names give the name of fear; as, for example, in the case of children there is a forgetfulness of their evils at the very time of their tears, for they change in a moment, and laugh and play along with those who were thought to grieve and terrify them, but in truth had wrought in them no such emotion.  So too, moreover, one will humble himself like the little child which Jesus called; for neither haughtiness, nor conceit in respect of noble birth, or wealth, or any of those things which are thought to be good, but are not, comes to a little child.  Wherefore you may see those who are not altogether infants, up to three or four years of age, like to those who are of mean birth, though they may seem to be of noble birth, and not appearing at all to love rich children rather than the poor.  If, therefore, in the same way as according to their age children are affected towards those passions which exalt the senseless, the disciple of Jesus under the influence of reason 5928 has humbled himself like the little child which Jesus showed, not being exalted because of vainglory, nor puffed up on the ground of wealth, or raiment, nor elated because of noble birth, in particular are they to be received and imitated in the name of Jesus, who have been converted as the Word showed, like the little child which Jesus took to Him; since especially in such the Christ is, and therefore He says, “Whosoever shall receive one such little child in My name receiveth Me.” 5929

Footnotes

2 Cor. iv. 10.

Or, the Word.

Matt. xviii. 5.