4:18 Jesus’s ministry throughout Galilee demonstrated that the Spirit of the Lord was on him (v. 14). As Messiah, he was anointed as the rightful king of Israel. But here the anointing was as a prophet (to preach good news). Even though the message Jesus preached was first to those who were captivated by sin, the mention of the poor … the captives … the blind, and the oppressed is in keeping with Luke’s emphasis on the poor and downtrodden.
4:18 Jesus reads from Is. 61:1, 2 and interpolates a phrase from Is. 58:6, following the LXX. By stopping in the middle of Is. 61:2, Jesus calls attention to “the acceptable year of the Lord,” which compares the blessings of His ministry to the ancient Year of Jubilee.
4:18. Jesus began to read from Isa 61:1 which identifies the Messiah as One empowered by the Holy Spirit, and then delineates His mission. Up to this point Luke has not recorded any of Jesus’ miraculous works. His ensuing ministry would validate His Messiahship.
4:18 “This is a partial quote of Isa. 61:1–2 from the Septuagint with the omission of verses 1c and 2b, but with an insertion of a verse from Isa. 58:6d. The combining and editing of OT texts was common in rabbinical Judaism.
“The Spirit of the Lord is upon Me” Notice the different divine Persons. See Special Topic: The Trinity at 3:22. The new age of righteousness is the Age of the Spirit.
“He anointed Me” This Hebrew word is the same root as “Messiah.” In Greek the term “Messiah” is translated “Christ.” This was a way of denoting God’s calling and equipping of leaders. In the OT prophets, priests, and kings were anointed. See Special Topic: Anointing in the Bible at 2:11.
“preach the gospel” At this point the full gospel is not yet available. Only after Jesus’ death and resurrection did His actions and teachings come into perfect focus.
“poor … captives … blind … downtrodden” Notice the types of people that Jesus came to help. His care for these fulfilled many prophetic texts.
18. The Spirit of the Lord is upon me. These words inform us that, both in his own person and in his ministers, Christ does not act by human authority, or in a private capacity, but has been sent by God to restore salvation to his Church. He does nothing by the suggestion or advice of men, but everything by the guidance of the Spirit of God; and this he declares, in order that the faith of the godly may be founded on the authority and power of God. The next clause, because he hath anointed me, is added by way of explanation. Many make a false boast, that they have the Spirit of God, while they are destitute of his gifts: but Christ proves by the anointing, as the effect, that he is endued with the Spirit of God. He then states the purpose for which the graces of the Spirit were bestowed upon him. It was, that he might preach the Gospel to the poor. Hence we conclude, that those, who are sent by God to preach the Gospel, are previously furnished with necessary gifts, to qualify them for so important an office. It is, therefore, very ridiculous that, under the pretence of a divine calling, men totally unfit for discharging the office should take upon themselves the name of pastors. We have an instance of this in the Papacy, where mitred bishops, who are more ignorant than as many asses, proudly and openly vaunt, that they are Christ’s Vicars, and the only lawful prelates of the Church. We are expressly informed, that the Lord anoints his servants, because the true and efficacious preaching of the Gospel, as Paul says, does not lie “in the enticing words of man’s wisdom,” but in the heavenly power of the Spirit.
To the poor. The prophet shows what would be the state of the Church before the manifestation of the Gospel, and what is the condition of all of us without Christ. Those persons to whom God promises restoration are called poor, and broken, and captives, and blind, and bruised. The body of the people was oppressed by so many miseries, that these descriptions applied to every one of its members. Yet there were many who, amidst their poverty, blindness, slavery, and death, flattered themselves, or were insensible to their condition. The consequence was, that few were prepared to accept this grace.
And, first, we are here taught what is the design of the preaching of the Gospel, and what advantage it brings to us. We were altogether overwhelmed by every kind of evils: but there God cheers us by his life-giving light, to rescue us from the deep abyss of death, and to restore us to complete happiness. It tends, in no ordinary degree, to recommend the Gospel, that we obtain from it inestimable advantage. Secondly, we see who are invited by Christ, and made partakers of promised grace. They are persons, who are every way miserable, and destitute of all hope of salvation. But we are reminded, on the other hand, that we cannot enjoy those benefits which Christ bestows, in any other manner, than by being humbled under a deep conviction of our distresses, and by coming, as hungry souls, to seek him as our deliverer: for all who swell with pride, and do not groan under their captivity, nor are displeased with their blindness, lend a deaf ear to this prediction, and treat it with contempt.
Ver. 18.—The Spirit of the Lord is upon me. St. Luke here quotes, with a few unimportant variations, from the LXX of Isa. 61:1, 2. The clause, “to set at liberty them that are bruised,” does not occur in the present text of Isaiah. The bright, comforting words of the great prophet the Lord chose as giving a general summary of what he designed to carry out in his ministry. It could be no undesigned coincidence that the opening words of the passage contain a singularly clear mention of the three Persons of the blessed Trinity—the Spirit, the Father, and the Anointed (Messiah). Because he hath anointed me to preach the gospel to the poor, etc. The common interpretation referred this passage to the state of the people on the return from the Captivity. Nothing, however, that the people had yet experienced in any way satisfied the brilliant picture painted in the great prophecy. A remnant certainly had returned several centuries back from their distant exile, but the large majority of the chosen people were scattered abroad; their own land was crushed under what seemed a hopeless servitude; poverty, ignorance, universal discontent, reigned alike in Jerusalem, garrisoned with Roman legionaries, and in the most distant of the poor upland villages of Galilee. Only could deliverance come and a golden age of prosperity return with the promised Messiah. This was the interpretation which the choicest spirits in Israel applied to the great Isaiah prophecy read that sabbath day in the little synagogue of Nazareth. This was the meaning which Jesus at once gave to it, only he startled his hearers by telling them that in him they saw the promised long-looked-for Deliverer. We only possess, it is evident, the very barest abstract of the words of the Teacher Jesus on this occasion. They must have been singularly eloquent, winning, and powerful to have extorted the wonder and admiration alluded to in the twenty-second verse.
4:18 The Spirit of the Lord is on me. The opening of the Isaiah text echoes Jesus’s experience at 3:22, which has already been reiterated in Luke’s comment that Jesus began his ministry “in the power of the Spirit” (4:14). The following clauses make it clear that this endowment is specifically for the unique mission of preaching and deliverance that Jesus has come to fulfill, as he will declare in 4:21.
There is no record that Jesus literally freed prisoners (though such events will occur in Acts 5:19; 12:6–11), and Luke is probably thinking here of Jesus’s exorcisms (of people “held captive” by a demon) and healings (note the language of “setting free” in 13:16). But the later history of Jesus’s followers contains fine examples of the literal application of this principle, notably in relation to the abolition of slavery.
4:18 / The Spirit of the Lord is on me … he has anointed me: Tannehill (pp. 58–59, 62–63) has argued that Jesus’ anointing (which refers back to the baptism, 3:22) is royal, not simply prophetic (contra Fitzmyer, pp. 529–30). I agree. It is his anointing that makes Jesus “Messiah,” and in being presented as Messiah, Jesus is presented as David’s successor, Israel’s long-awaited king.
18 The “good news” Jesus was to proclaim recalls both the joyful announcement in 1:19 and the frequent use of the term elsewhere in Luke. It also builds on Isaiah 40:9; 41:27; and especially 52:7. The concerns for the “poor,” like the “prisoners,” the “blind,” and the “oppressed,” point then to Luke’s (and Isaiah’s) focus on the theme of reversal when those humbled ones will be blessed (see comments at 1:53; 6:20).
 Calvin, J., & Pringle, W. (2010). Commentary on a Harmony of the Evangelists Matthew, Mark, and Luke (Vol. 1, pp. 228–229). Logos Bible Software.