Acts 1:8

“But you shall receive power, when the Holy Spirit is come on you: and you shall be my witnesses both in Jerusalem, and in all Judaea and Samaria, and to the uttermost part of the earth.”

What they are to spend their thoughts and concentration on is now outlined. The very purpose of the coming of the Holy Spirit, is so that they might receive power to become His witnesses by both personal witness and godly living. That witness was first to be in Jerusalem, and then ‘in Judaea and Samaria' (in the Greek closely conjoined), and then in the uttermost parts of the earth. By witnessing to Him they would be establishing His Kingly Rule (Acts 8:12; Acts 14:22; Acts 19:8; Acts 20:25; Acts 28:23; Acts 28:31; Romans 14:17; 1 Corinthians 4:20).

These words were an indication to them that they had no time for speculation, and that His coming could certainly not take place for a good long time (He had gone into a far country), during which time they must reach the whole world for Christ (even though they would think in terms of the Roman world, compare Romans 1:8; Romans 16:19; Colossians 1:6). As He had previously informed them, His coming would not happen until Jerusalem had been destroyed (Matthew 24; Mark 13; Luke 21). Meanwhile they must be active.

‘You shall be my witnesses.' The idea behind the word ‘witness' is that of being able to declare something experienced personally, to declare something experienced at first hand. In the first initial surge the witness in mind especially included those who had been eyewitnesses, both of Jesus' earthly life and of His resurrection. The importance lying behind this is brought out in the following verses by the electing to the twelve of another eyewitness of both. But secondarily it includes the witness of all who have personally experienced His saving power.

The word ‘witness' occurs continually throughout Acts, and can be considered as one of its main themes. This was to be the purpose of the church, to be a witness to Jesus as the risen and enthroned Christ and Lord, and to His Kingly Rule.

It should be noted here that as far as they were concerned at that point in time this meant that they had to go out among the Jews of the Dispersion (including proselytes, (converted Gentiles who has been circumcised) and possibly God-fearers (Gentiles who attended the synagogue because attracted by the moral teaching of the Jewish Scriptures and the idea of one God but who were not willing to be circumcised) so that all of them might hear about Jesus their Messiah and Lord. Jesus did not go into explanations, at this point in time, as to the exact meaning of His words. As with His comment about the time of the coming kingdom, details could be left until later truth dawned on them. It would not be until much later that it came home to them that it also included untouched Gentiles.

‘To the uttermost part of the earth (heows eschatou tes ges).' This phrase is rare in ancient Greek literature, but it occurs four times in Isaiah in the Septuagint (Isaiah 8:9; Isaiah 48:20; Isaiah 49:6; Isaiah 62:11). In Isaiah 8:9 it refers to far off nations, in Isaiah 48:20 it refers to the declaring to ‘the end of the earth' that Yahweh has ‘redeemed His servant Jacob', in Isaiah 49:6 the Servant of Yahweh is to be given for a light to the Gentiles that He may ‘be for Yahweh's salvation to the end of the earth', in Isaiah 62:11 Yahweh ‘proclaims to the end of the earth', “Say you to the daughter of Zion, Behold your salvation comes. Behold your reward is with Him, and His recompense before Him, and they will call you the holy people, the redeemed of Yahweh, and you shall be called ‘Sought out', a city nor forsaken”.

It seems therefore probable that Jesus would expect His disciples to connect the phrase with Isaiah, and recognise that He was saying that in witnessing to Him ‘to the end of the earth' they would be declaring God's salvation as expressed in Isaiah and proclaiming that He had now come to redeem His people. They probably initially thought more in terms of Isaiah 48:20; Isaiah 62:11 with their emphasis on the message of salvation going to the Jews worldwide, but once the full truth of their mission came home they would also relate it to the work of the Servant on behalf of the Gentiles in Isaiah 49:6. This particularly comes out in that in Acts 13:47 they not only see the Servant as Jesus, but also as the witnessing church, in a verse where Isaiah 49:6 is quoted. This latter verse confirms that this was their final view.

We should note here that similar instructions had already been given to them a number of times, along with further definition of how they should go about it. ‘Go -- and make disciples of all nations ---' (Matthew 28:19). ‘Go into all the world and preach the Good News to the whole creation ---' (Mark 16:15). ‘Repentance and remission of sins should be preached in His name to all the nations, beginning from Jerusalem. You are witnesses of these things' (Luke 24:47). Now they were to learn how to interpret it.