He read Esaias. The reading of the prophet showeth that the eunuch did not worship a God unadvisedly, according to the understanding of his own head, whom he had reigned to himself, but whom he knew by the doctrine of the law. And surely this is the right way to worship God, not to snatch at bare and vain rites, but to adjoin the word thereunto, otherwise there shall be nothing but that which cometh by chance and is confused. And certainly the form of worshipping prescribed in the law differeth nothing from the inventions of men, save only because God giveth light there by his word. Therefore, those which are God's scholars do worship aright only, that is, those who are taught in his school. But he seemeth to lose his labor when he readeth without profit. For he confesseth that he cannot understand the prophet's meaning, unless he be helped by some other teacher. I answer, as he read the prophet with a desire to learn, so he hoped for some fruit, and he found it indeed. Therefore, why doth he deny that he can understand the place which he had in hand? For because [1] he manifestly confesseth his ignorance in darker places. There be many things in Isaiah which need no long exposition, as when he preacheth of the goodness and power of God, partly that he may invite men unto faith, partly that he may exhort and teach them to lead a godly life. Therefore, no man shall be so rude an idiot [2] which shall not profit somewhat by reading that book, and yet, notwithstanding, he shall, peradventure, scarce understand every tenth verse. Such was the eunuch's reading. For seeing that, according to his capacity, he gathered those things which served to edification, he had some certain profit by his studies. Nevertheless, though he were ignorant of many things, [3] yet was he not wearied, so that he did cast away the book. Thus must we also read the Scriptures. We must greedily, and with a prompt mind, receive those things which are plain, and wherein God openeth his mind. As for those things which are hid from us, we must pass them over until we see greater light. And if we be not wearied with reading, it shall at length come to pass that the Scripture shall be made more familiar by continual use.

Footnotes

1 - "Nempe... agnoscit," namely, he acknowledgeth.

2 - "Idiota," unlearned.

3 - "Si multa eum latebant," though many things escaped him, were hidden from him.

And, sitting in his chariot - His carriage; his vehicle. The form of the carriage is not known. In some instances the carriages of the ancients were placed on wheels; in others were borne on poles, in the form of a "litter" or palanquin, by men, mules, or horses. See Calmet's "Chariot" article.
Reading Esaias - Isaiah. Reading doubtless the translation of Isaiah called the Septuagint. This translation was made in Egypt for the special use of the Jews in Alexandria and throughout Egypt, and was what was commonly used. "Why" he was reading the Scriptures, and especially this prophet, is not certainly known. It is morally certain, however, that he was in Judea at the time of the crucifixion and resurrection of Jesus; that he had heard much of him; that this would be a subject of discussion; and it was natural for him, in returning, to look at the prophecies respecting the Messiah, either to meditate on them as a suitable subject of inquiry and thought, or to examine the claims of Jesus of Nazareth to this office. The prophecy in Isaiah 53:1-12; was so striking, and coincided so clearly with the character of Jesus, that it was natural for a candid mind to examine whether "he" might not be the person intended by the prophet. On this narrative we may remark:
(1) It is a proper and profitable employment, upon returning from "worship," to examine the Sacred Scriptures.
(2) it is well to be in the habit of reading the Scriptures when we are on a journey. It may serve to keep the heart from worldly objects, and secure the affections for God.
(3) it is well at all times to read the Bible. It is one of the means of grace. And it is when we are searching his will that we obtain light and comfort. The sinner should examine with a candid mind the sacred volume. It may be the means of conducting him in the true path of salvation.
(4) God often gives us light in regard to the meaning of the Bible in unexpected modes. How little did this eunuch expect to be enlightened in the manner in which he actually was. Yet God, who intended to instruct and save him, sent the living teacher (Philip), and opened to him the Scriptures, and led him to the Saviour.

Sitting in his chariot, read Esaias the prophet - He had gone to Jerusalem to worship: he had profited by his religious exercises: and even in travelling, he is improving his time. God sees his simplicity and earnestness, and provides him an instructer, who should lead him into the great truths of the Gospel, which, without such a one, he could not have understood. Many, after having done their duty, as they call it, in attending a place of worship, forget the errand that brought them thither, and spend their time, on their return, rather in idle conversation than in reading or conversing about the word of God. It is no wonder that such should be always learning, and never able to come to the knowledge of the truth.

Was returning,.... From Jerusalem, having finished the parts of divine worship he came to perform; and it is remarkable, that though he must doubtless have heard of Jesus of Nazareth, and what had passed in Jerusalem lately, and of his apostles, yet heard them not; or however, was not converted by them, nor believed in Jesus; his conversion being ordered to be at another time, in another place, and by another instrument:
and sitting in his chariot: as was the manner of princes and great persons:
read Esaias the Prophet; the Book of the Prophecies of Isaiah the Prophet; and in Luke 4:17 it is called the "Book of the Prophet Esaias"; and in the note there; see Gill on Luke 4:17, I have observed, that the prophets, especially the larger ones, were sometimes in separate and distinct books, and so might be the prophecy of Isaiah; and such an one was delivered to Christ, in the synagogue of Nazareth; and such an one the eunuch might have, and be reading in it: hence we read (s), that Daniel should say to the Israelites, who came to discourse with him about the prophecies of Jeremiah, bring me, says he, , the Book of Isaiah"; he began to read, and went on till he came to this verse, "the burden of the desert of the sea", &c. Isaiah 21:1 and both the Arabic and Ethiopic versions here read, "the Book of the Prophet Isaiah." See Gill on Luke 4:17. Some think the eunuch might be reading over some passages of Scripture in this prophet, which he had heard expounded at Jerusalem, to refresh his memory with what he had heard. This prophet is a very evangelical one, and very delightful and profitable to read: many things are prophesied by him concerning the Messiah, and particularly in the chapter in which the eunuch was reading; and this being a time when there was great expectation of the Messiah, such passages might be read and expounded in their synagogues, which concerned him: however, the eunuch improved his time, as he was travelling in a religious way, which was very commendable; and as this was the occasion and opportunity which the Holy Ghost took to bring on his conversion, it may serve greatly to recommend the reading of the Scriptures.
(s) Shirhashirim Rabba, fol. 33. 1.

Was returning--Having come so far, he not only stayed out the days of the festival, but prolonged his stay till now. It says much for his fidelity and value to his royal mistress that he had such liberty. But the faith in Jehovah and love of His worship and word, with which he was imbued, sufficiently explain this.
and sitting in his chariot, read Esaias--Not contented with the statutory services in which he had joined, he beguiles the tedium of the journey homeward by reading the Scriptures. But this is not all; for as Philip "heard him read the prophet Esaias," he must have been reading aloud and not (as is customary still in the East) so as merely to be audible, but in a louder voice than he would naturally have used if intent on his own benefit only: evidently therefore he was reading to his charioteer.

Was returning and . . . reading. Reading aloud in the Oriental manner. Perhaps he had heard at Jerusalem of Jesus and the Christians. At any rate, he was reading in Isaiah a prophecy of Christ.

Sitting in his chariot, he read the Prophet Isaiah - God meeteth those that remember him in his ways. It is good to read, hear, seek information even in a journey. Why should we not redeem all our time?