Matthew 18:2 - Joseph Benson’s Commentary on the Old and New Testaments

And Jesus Perceiving the thought of their heart, says Luke, or the dispositions by which they were animated, and their ambitious views and expectations; in order to check and eradicate all such sinful inclinations and affections, he called a little child, and set him in the midst of them That they might consider him attentively, and learn by the sweetness, docility, and modesty visible in his countenance, what the temper and dispositions of his disciples ought to be, and how dear to him persons of such dispositions are. This little child is said to have been the great Ignatius, whom Trajan the wise, the good Emperor Trajan, condemned to be cast to the wild beasts at Rome! This method of instruction was agreeable to the manner of the eastern doctors and prophets, who, in teaching, impressed the minds of their disciples by symbolical actions, as well as by words. Thus, John 20:22, Jesus, by breathing on his apostles, signified that through the invisible energy of his power he conferred on them the gifts of his Spirit. Thus also, John 21:19, he bade Peter follow him, to show that he should be his follower in sufferings. And, Revelation 18:21, an angel cast a great stone into the sea, to signify the utter destruction of Babylon.