18:1 After this [refers to Paul’s experience at Athens (Acts 17:16-34)], Paul left Athens and went to Corinth [a seaport city and major commercial site; had reputation of being extremely wicked; temple of Aphrodite located in Corinth].
18:2 There he met [a providential meeting] a Jew named Aquila, a native of Pontus [a province in northeastern Asia Minor; people from Pontus present during Peter’s sermon at Pentecost (Acts 2:9)], who had recently come from Italy with his wife Priscilla [or Prisca], because Claudius [emperor in AD 41-54] had ordered all the Jews to leave Rome. Paul went to see them,
18:3 and because he was a tentmaker as they were, he stayed and worked [Paul supported himself in Corinth] with them [must have been a blessing for Paul to have a Christian haven in such an immoral city].
Note: What are you doing to encourage your spiritual leaders in the work that God has called them to do? How do you think Paul’s presence benefited Aquila and Priscilla?
18:4 Every Sabbath he reasoned in the synagogue, trying to persuade Jews and Greeks.
18:5 When Silas and Timothy [brought good news about the Christians at Thessalonica (cf. 1 Thess. 3:6)] came from [to join Paul in Corinth] Macedonia [province included towns of Thessalonica, Berea, Philippi; probably bringing an offering from Philippi (cf. 2 Cor. 11:9 and Phil. 4:14-16) or all of the churches in Macedonia], Paul devoted himself exclusively [wholly absorbed in; likely possible because of the offering brought by Silas and Timothy] to preaching, testifying [to solemnly declare] to the Jews that Jesus was the Christ.
Note: What impact do our financial gifts have on the lives of those serving in other countries?
18:6 But when the Jews opposed [resisted] Paul and became abusive [to slander, to blaspheme], he shook out [cf. Matt. 10:14 re: shaking dust off feet] his clothes [an act symbolizing exemption from further responsibility for them] in protest and said to them [cf. Ezek. 33:1-7], “Your blood be on your own heads [for rejecting the precious pearl of the gospel (cf. Matt. 7:6)]! I am clear of my responsibility [those who opposed Paul were responsible for any coming judgment]. From now [a turning point in Paul’s ministry; Paul changed course] on I will go [to those who are receptive] to the Gentiles [cf. Acts 13:44-46 re: Paul turning from synagogue to Gentiles in Pisidian Antioch].”
18:7 Then [Paul did not quit because of the opposition and abuse he had previously encountered in the synagogue (cf. v. 6)] Paul left the synagogue and went next door [to be right next to, to adjoin] to the house of Titius Justus [a place where both Jews and Gentiles were welcome; became the first meeting place of the Corinthian church; possibly Gaius mentioned in Rom. 16:23 and 1 Cor. 1:14], a worshiper of God [God-fearer; perhaps Titius Justus had heard Paul speak in the synagogue (cf. v. 4) and was later saved].
18:8 Crispus [a Jew (indicates that Paul continued his witness to Jews); one of the first to receive Paul’s message; baptized by Paul as per 1 Cor. 1:14; cf. 1 Cor. 16:15 re: Stephanas, the first believer at Corinth], the synagogue ruler [responsible to maintain facility and appoint men to lead service], and his entire household believed in the Lord; and [perhaps because of the conversion of Crispus] many of the Corinthians who heard him [pronoun is indefinite: could refer to Paul or Crispus] believed and were baptized.
18:9 One night the Lord spoke to Paul in a vision [divine encouragement; this vision may indicate that Paul had become discouraged by the opposition, the immorality of the city, and perhaps, loneliness; this vision strengthened Paul for what lay ahead]: “Do not [stop an action in progress] be afraid [perhaps fear of persecution; cf. Jn. 16:33]; keep on speaking, do not be silent.
18:10 [reassurance of God’s protection; note two promises]  For I am [words of assurance] with you [cf. Rom. 8:31; His presence dispels fear], and no one is going to attack and harm you [protected from but not free from difficulties], because  I have many people in this city [Corinth; i.e., many people in the city were or were to be Christ’s own].”
18:11 So [because of the assurance Paul received in the vision (cf. vv. 9-10)] Paul stayed [in Corinth] for a year and a half [probably from the fall of 50 to the spring of 52], teaching them the word of God [and consequently establishing a large church there].
18:12 While Gallio was proconsul [oversaw administration of civil/military matters in province; appointed by Roman senate] of Achaia [consisted of southern half of ancient Greece; major cities included Sparta, Athens, Corinth], the Jews made [rose up against] a united attack on Paul and brought him into court.
18:13 “This man,” they charged, “is persuading [to seduce, to mislead; suggests that Paul was successful at persuading] the people to worship God in ways contrary to the law [Roman law; Paul charged with preaching a religio illicita — an illegal religion, and therefore acting contrary to Roman law].”
18:14 Just as Paul was about to speak, Gallio said to the Jews, “If you Jews were making a complaint about some misdemeanor or serious crime [rather than a charge of breaking Jewish religious law], it would be reasonable for me to listen to you.
18:15 But since it involves questions about words [possibly reference to Scriptures] and names [possibly reference to name of Jesus] and your own law [not Roman law; not a matter that threatened Roman rule] — settle the matter yourselves. I will not be a judge of such things. [Gallio’s decision was tantamount to the recognition of Christianity as a religio licita]“
18:16 So he had them [Jewish religious leaders and Paul] ejected [a rebuke to Jewish religious leaders; this made it possible for Paul to continue his ministry without fear of Roman interference] from the court.
18:17 Then they all turned on Sosthenes the synagogue ruler and beat him in front of the court. But Gallio showed no concern whatever.
18:18 Paul stayed on in Corinth for some time. Then he left the brothers and sailed for Syria, accompanied by Priscilla and Aquila. Before he sailed, he had his hair cut off at Cenchrea because of a vow [a temporary Nazirite vow or a personal vow of thanksgiving] he had taken.
18:19 They arrived at Ephesus, where Paul left [this couple settled in Ephesus, perhaps to help champion the cause of Christ in Asia] Priscilla [named first in four of the six times this couple is mentioned in the NT] and Aquila [always named together as a couple and never individually in the NT]. He himself went into the synagogue and reasoned with the Jews.
18:20 When they asked him to spend more time with them, he declined.
18:21 But as he left, he promised, “I will come back if it is God’s will.” Then he set sail from Ephesus.
18:22 When he landed at Caesarea, he went up and greeted the church and then went down to Antioch [the end of Paul’s second missionary journey].
18:23 After spending some time in Antioch, [the beginning of Paul’s third missionary journey (AD 53–57)] Paul set out from there and traveled from place to place throughout the region of Galatia and Phrygia, strengthening [establishing or making strong] all the disciples.
18:24 Meanwhile [while Paul was en route to Ephesus] a Jew named Apollos, a native of Alexandria [founded by and named for Alexander the Great in 332 BC; capital of Egypt and home to one of the greatest libraries of the ancient world; the Septuagint (Gr. translation of OT) was translated there], came to Ephesus. He was  a learned man [indicates he was well-educated], with  a thorough [comprehensive grasp of both the content and the meaning] knowledge of the Scriptures [OT books].
Acts 18:23 marks the beginning of Paul’s third missionary journey. Paul set out from Antioch and revisited his former mission fields. While Paul was traveling, a man named Apollos arrived in Ephesus. Apollos was from the Egyptian city of Alexandria. Founded by and named for Alexander the Great, Alexandria was the second largest city in the Roman Empire and boasted one of the largest libraries of the ancient world. Apollos was an eloquent or well-educated man who had a powerful or comprehensive understanding of the Scriptures.
18:25  He had been instructed in the way of the Lord [had heard about Jesus and was familiar with His teachings], and  he spoke with great fervor [passionate and zealous] and  taught about Jesus accurately [carefully], though he knew only the baptism of John [probably taught the concept of baptism as a symbol of repentance; not familiar with Christian baptism; perhaps knew nothing of the coming of the Spirit at Pentecost].
Apollos had been instructed in the way of the Lord and was familiar with His teachings. We are not told who had instructed him. Presumably, he had learned about Jesus through disciples of John the Baptist. Apollos was fervent in spirit or enthusiastic, a word that means to be inspired or to be “in God.” He was a passionate orator who taught what he knew about Jesus with accuracy. The only problem was that his understanding of the gospel was incomplete. He knew only of John’s baptism but nothing of what had happened at Pentecost.
18:26 He began to speak boldly in the synagogue. When Priscilla and Aquila heard him, they [they obviously saw potential in Apollos] invited him to their home [just as they had used their home to minister to and with Paul (Acts 18:3)] and explained [indicates Aquila and Priscilla were mature in their understanding and experience of the gospel; they had likely learned much from Paul when he had stayed in their home in Corinth] to him the way of God [refers either to the gospel itself or to some application of the gospel to Christian living or some aspects of Christian doctrine] more adequately [or “more perfectly”].
Priscilla and Aquila heard Apollos speak about Jesus in the synagogue. Listening to what people say about Christianity, especially those open to the gospel, will help us know how complete their understanding is and how to help them. Priscilla and Aquila recognized that this gifted orator named Apollos had an incomplete knowledge of the gospel. Rather than correct him in public, they invited him to their home.
Earlier, they had extended the same kind of hospitality to Paul, who had stayed and worked in their home in Corinth (see Acts 18:3). Priscilla and Aquila must have learned much from Paul during that time. Now, they took the time to explain the way of God to Apollos more accurately. Presumably, they told him more about Jesus’ life, death, and resurrection, as well as about the coming of the Holy Spirit. This committed couple used their home as a tool for spreading the gospel (see Rom. 16:3-5) and for strengthening believers.
Note: Who has been a mentor to you in ministry? How has that person encouraged you in your service to the Lord? To whom are you acting as a mentor?
18:27 When Apollos [showed himself to be a humble person who was open to be taught by Aquila and Priscilla; Paul always spoke highly of Apollos (cf. 1 Cor. 1:12; 3:4-6; 4:6; 16:12; Titus 3:13); an Apollos faction became one of the splinter groups in Corinth (1 Cor. 1:12)] wanted to go to Achaia [the region of Greece where Corinth is located; northwest from Ephesus across the Aegean Sea], the brothers [the Christians at Ephesus] encouraged him and wrote [a letter of introduction or recommendation] to the disciples there [Corinth] to welcome him. On arriving, he was a great help to those who by grace had believed.
The time Apollos spent with Aquila and Priscilla was profitable. He humbly received their instruction and gained a better understanding of the gospel. Soon after, Apollos wanted to travel to Achaia, the region of Greece where Corinth is located. We are not told why he decided to go there. One reason may be that Aquila and Priscilla had aroused his interest in Corinth by telling him of Paul’s experiences there. The brothers at Ephesus wrote a letter of introduction to the disciples there, urging them to welcome the gifted apologist and orator. Apollos proved to be a great help to those who had believed by grace.
18:28 For he vigorously refuted the Jews in public debate, proving from the Scriptures that Jesus was the Christ [the Messiah].
Apollos had a brilliant mind and was an excellent debater. He used the Scriptures to convince many unbelieving Jews in Corinth that Jesus was indeed the long-awaited Messiah. Like Stephen, Apollos was an excellent Christian apologist—a term that refers to a person who argues in defense of what he or she believes. Christians today must study the Scriptures and develop the ability to intelligently speak to others about what they believe and why they believe it.