From the early Church Fathers to now.
4 Patristic · 1 Orthodox
“And Philip running thither, heard him reading the prophet Isaias. And he said: Thinkest thou that thou understandest what thou readest?”
“He was not ashamed to confess his ignorance and implored to be taught. Therefore, to him who became a learner, the grace of the Spirit was given. But as for those Jews who persisted in their ignorance; as the proverb says, "Death came upon them. For the fool dies in his sins."”
“I mean, when the apostle said, "Do you really understand?" and came close in his lowly condition, he was not put off, he made no objection, he did not consider himself disgraced in the way many foolish people react, often preferring to remain in unbroken ignorance through a sense of shame in admitting their ignorance and having to learn from those able to instruct them.”
“Observe the wisdom of Philip: he did not accuse him, not say, "I know these things exactly:" did not pay court to him, and say, "Blessed art thou that readest." But mark his speech, how far it is from harshness alike and from adulation; the speech rather of a kind and friendly man. "Understandest thou what thou readest?" For it was needful that he should himself ask, himself have a longing desire. He plainly intimates, that he knows that the other knew nothing: and says, "Understandest thou what thou readest?" at the same time he shows him that great was the treasure that lay therein.”
“It tells well also, that the eunuch looked not to the outward appearance of the man, said not, "Who art thou?" did not chide, not give himself airs, not say that he did know. On the contrary, he confesses his ignorance: wherefore also he learns. He shows his hurt to the physician: sees at a glance, that he both knows the matter, and is willing to teach. Look how free he is from haughtiness; the outward appearance announced nothing splendid. So desirous was he of learning, and gave heed to his words; and that saying, "He that seeketh, findeth," was fulfilled in him.”
“"Do you understand what you are reading?" He asks in a wonderful manner, because he neither flatters, nor praises, nor reproaches him for ignorance. But he asks in such a way as to arouse greater desire and to show that in what is being read there lies a great treasure.”
The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.