2:1 day of Pentecost. “Pentecost,” meaning “fifty days,” was a festival observed fifty days after the feast of firstfruits, which was held on a sabbath day. The feast of firstfruits (Leviticus 23:9-14) was actually prophetic of the resurrection of Christ (I Corinthians 15:20), which also had taken place on the first day of the week. Thus Pentecost was held on the first day of the week, and it was on such a day that the Holy Spirit came to indwell the church. Quite possibly this fact played a part in the gradual adoption by the churches of the first day of the week as their regular day of rest and worship (note Acts 20:7; I Corinthians 16:2). The weekly observance of the sabbath was in commemoration of the completion of God’s work of creation (Genesis 2:1-3; Exodus 20:8-11), but God’s great work of redemption was now also completed (John 19:30). Thus, by observing their weekly “sabbath day” (“rest day”) on the first day of the week, they would be honoring the completion of both God’s work of creation and His work of redemption. Pentecost also commemorated the giving of the law at Mount Sinai, which occurred fifty days after the Passover (Exodus 12:6; 19:1,11).

2:2 filled all the house. The mighty wind, representing the coming of the Spirit, “filled all the house” the house; the baptism (i.e., “immersion”) by the Spirit thus was emphasized symbolically when the Lord Jesus first sent Him, fulfilling His promises (e.g., John 7:39; 14:16).

2:3 tongues like as of fire. These mysterious cloven tongues seem to depict a fiery root, divided into many individual tongues, enough to reach each person in the company. They were not real fire, however, but “like as of fire.” There have been various speculations as to their nature, but since it was a supernatural phenomenon, these seem pointless. In any case, the mighty wind filling the house and the fire-like tongues reaching each of the company are the audible and visible signs that the Holy Spirit had come, baptizing and filling all of them, fulfilling John the Baptist’s prophecy that Christ would baptize them “with the Holy Ghost and with fire” (Luke 3:16).

2:4 filled with the Holy Ghost. Although the Spirit’s baptism and filling occurred simultaneously in this initial manifestation of His power, the two are separate ministries. All believers are baptized by the Holy Spirit into the body of Christ once for all at the time of conversion (I Corinthians 12:13). They can, however, be filled with the Spirit on more than one occasion and, in fact, are exhorted to “be [continually being] filled with the Spirit” (literal reading of Ephesians 5:18). Note, for example, the repeated fillings recorded in Acts 4:8,31; 9:17; 13:9.

2:4 other tongues. These were “other tongues,” not “unknown tongues” or “ecstatic tongues.” Except when referring to the actual physical organ, the word “tongue” in the New Testament always refers to a language. In this case, the tongues are the actual languages of the different nations listed in Acts 2:9-11, as made obvious in the context.

2:5 dwelling at Jerusalem. The verb here does not convey the meaning of temporary lodging, as though these men had just come to Jerusalem for the feast days, but rather permanent dwellings. These were devout Jews, who had decided, for religious reasons, to move back to Jerusalem from the various foreign lands where they had been raised (Acts 2:8), their ancestors having been deported from Israel in earlier times. There may also have been temporary visitors from these other lands, lodging during the feast days with their Jerusalem friends and relatives.

2:11 Cretes and Arabians. Altogether, there are seventeen different nations or ethnic groups mentioned in Acts 2:9-11. This seems to be a number of some spiritual significance as representing all the world’s nations. See notes on John 21:11.

2:11 tongues. These Jews from the different nations could undoubtedly speak Aramaic, for they later comprehended Peter’s sermon (Acts 2:14-36), but they were amazed that the 120 Spirit-filled believers were preaching also in the languages of their homelands. This was a miraculous work of the Holy Spirit that not only authenticated the gospel, here being preached for the first time after Christ’s resurrection, but also emphasized that God no longer was dealing explicitly with the Jews, but with all nations.

2:13 mocking. This was a sarcastic reference to the fact that the followers of Jesus were well known to eschew drunkenness, and therefore would drink only new wine (that is, freshly pressed wine, still unfermented). They could not understand them, and assumed they were speaking gibberish, like drunkards might, and so used this as an excuse to mock their stand.

2:16 this is that. Peter here assures these devout Jews that this strange set of phenomena (the wind, the cloven tongues like fire, the preaching in many languages) was not an occult pagan manifestation of some kind, but an actual fulfillment of an important Old Testament prophecy, as found in Joel 2:28-32.

2:17 in the last days. This “last days” prophecy of Joel was fulfilled at Pentecost only in a precursive sense. Its complete fulfillment must await the time of the end (see its continuation in Joel 3). Thus Peter’s statement: “This is that” (Acts 2:16) should be understood in the sense of “This is like that.”

2:21 whosoever shall call. This application of Joel’s prophecy, as found in Joel 2:32, is valid in both its precursive and final fulfillments. See also Paul’s use of it in Romans 10:13.