What is the Church? To ask this question is almost to ask a similar question concerning God's kingship and kingdom. God is king over all things in relation to his creation, He is completely sovereign. "His Kingdom ruleth over all" (Ps. 103:19). God's Kingdom (Heb. Malkuth) is his kingly rule. There is the kingly rule of His power in nature, and the kingly rule of His grace amongst men that are the recipients of his special grace (Exodus 19:6). Even in His complete sovereignty God shares His kingly rule in a limited sphere as a grace gift to those He chooses to make His servants (1Chron. 17:14).
The phrase "the kingdom of God" is frequent in the Gospels and that reminds us of the intense expectation surrounding this matter at that time. It was prophesied in connection with the coming of Messiah and it meant that instead of rebellion and disobedience, Israel would truly bow to the kingly rule of God's grace and therefore know the LORD's continued blessing (Matt 6:10). Messiah would bring the kingdom (Luke 11:20 & Mark 1:14-15).
The Prophets, however, spoke of only a remnant initially being formed by means of whom Israel would ultimately be saved (Jer. 23:3, Zech. 13:7-9, Micah 4:4-7 & 5:1-4, Is. 4; Is. 53:1). In Micah 4 the remnant becomes the seed or new root of Israel and determines the nature and form that it will take. Christ's phrase in Luke 12:32 (“it is your Father's good pleasure to give you the kingdom”) is based upon this and Daniel 7:22&27, which speaks of the kingdom being given to the saints of God. The remnant is not a new Israel rather it is the true Israel. The new covenant likewise is a renewed covenant rather than a discontinuous entirely separate “covenant. The true Israelite in the Old Testament was the one who had circumcised his heart as well as having been circumcised in the flesh (Rom. 2:28-29). Christ calls those true Israelites who imitated the faith of their father Abraham such as Nathanael. The true Israel remnant were always found in the Old Testament Israel (Rom. 9:6) but the promise of the gospel is that this remnant will be expanded entirely, recognised as the true Israel with unfaithful Israel cut off and the Gentiles brought in. The olive tree of the Church (Romans 11) remains the same, but the Gentiles have been “grafted in” and “made partakers”, with the true Israel of God.
Since the time of John the baptist, the kingdom was announced (Luke 16:16), Christ was coming to baptize Israel with spirit and fire (Matt 3:11-12): to baptize true Israel (the repentant remnant) with the Holy Spirit and unrepentant Israel with the fire of judgement. John the baptist was preaching in order to call out a repentant remnant, denying that merely genetic Israel (Abraham's genetic descendants) constituted the true Israel (Matt 3:9 & Luke 3:8). Josephus (a historian contemporary) tells us that John was "commanding the Jews...“to come together“ in Baptism". He was fulfilling Ezekiel 36:25 and Isaiah 52:15 amongst other prophecies, which is why he was thought to be claiming Messiahship or at least to be Elijah who would prepare Messiah's way (John 1:25).
Christ was building a new temple (John 2:19-210 on himself as the cornerstone (Isaiah 28:14-16, I Pet. 2:4-8). Christ calls his disciples and teaches them the true Law of Moses on a mount in a way corresponding to the giving of the law at Sinai. He reveals the true depth of the law - he becomes the new Moses as the greater Prophet (Mark 3:13&14, Matt 5:1ff. Acts 3:22; Deut 18:15-18). Christ chooses 12 from all of his disciples. They are the true representatives of Israel, when they sit down with Christ to the Last Supper that inaugurates the New Covenant in similarity to the Old Covenant covenant meal (Exod. 24:1-12 esp. v11, cp. Luke 22:14&29-30 & Matt 19:28.). The Transfiguration also mirrored Exodus 24 in the small group brought with Jesus to the mountain to to see the glory. The voice that spoke indicated the law was now being delivered to Israel through Christ, as Moses' presence confirmed. It was being delivered not through Moses as mediator, but Christ Himself.
Why does Christ gather 12 main disciples? Surely to represent Israel (12 tribes) and the remnant which is the true Israel (Luke 22:29-30) since judgement is to come upon the nation. The twelve were chosen for a reason, as instruments in God's hand so that the true vine of the true Israel would bring forth lasting fruit (John 15:16). The great complaint against Israel in the prophets was that they did not bring forth fruit, they were an empty vine (Isaiah 5). The twelve and the seventy (cp. Ex 24 – 70 elders) were brought (as the remnant) into the mystery of God's purposes (Mt 11:25; Luke 10:21) namely, the mystery of the kingdom of God (Mk 4:1; cp. Mt 13:16-17 and Luke 10:23-4).
Christ then sends out the twelve and the seventy. It is important to notice the significance of the seventy. These correspond to the Sanhedrin and to the seventy elders of Exodus 24. The sanhedrin numbered seventy one because the high priest was the head of it. The sanhedrin was the ultimate church court of Israel like a Synod or General Assembly it was the supreme court (2 Chron 19:8-9). Christ as high priest was issuing and commissioning a new sanhedrin for the true Israel. The sanhedrin was composed of priests, scribes or Levites and elders (mainly Pharisees). When we read of these together or some of them they are described as “scribes and elders or in the Jew's shorthand, simply “the Jews” - meaning the rulers of the Jews. Sometimes they are called either the “scribes” or “the elders” (Mk 7:1and 5). Christ calls his disciples sent forth “scribes” (Mt 13:52 and Mt 23:34). At a particular time of reformation, the elder-judges in the Old Testament were sent forth with authority to establish the law of God and teach it in all the cities of Israel (2 Chron 19:5-7). The seventy were appointed also to relieve the work of the twelve and to share it in the way that Moses shared it with the seventy elders (Exodus 18).
In Mark 6:30 a technical term is used - “apostle”. In Hebrew this was “sheliakh”, an officer appointed by the Sanhedrin to represent them – the sheliakh had legal authority, fully representing the council in an action, mission or place. An example of this is Saul of Tarsus who, as is not always realised, was converted from being a false apostle (sent by the Sanhedrin) to being a true apostle (sent by Christ) as well as being converted by grace. It was normal that these officers should be sent in at least two's when representing the senders in some activity. We see in Christ's sending out apostles to preach that he sent them out by two's, the apostles followed this pattern in the missionary activity recorded in Acts. The Mishnah states in this respect (as the Jewish book of practice) “he who is sent by a man is as he who sent him”. Thus Christ gives his authority to his disciples, saying “he that receiveth you, receiveth me” and “as the Father sent me, so send I you” (Mt 10:40; Jn 20:21; Luke 10:16). Paul also sees his role as the ambassador of Christ in this respect, that he stands in Christ's stead (2 Cor 5:20). The disciples were only to go to the lost sheep of the house of Israel (Mt 10:6), in fulfiilment of Isaiah 40:9-11; 52:7&9). The apostles were given authority, full power over the evils of demons and diseases. The fact that Christ spoke through the disciples and the apostles (Eph 2:16-17) was attested by the miracles that he performed through them (Acts 2:33; Hebrews 2:3-4).
The Church is the true Israel only because Christ himself is the true Israel (Hos. 11:1; cf. Mt. 2:15). He is Abraham's seed (Gal. 3:16). Christ came born of a woman, born under law (Gal. 4:4), as the true Israel who would obey the commandments of God by perfectly keeping the covenant (Mt. 2:14-21) and suffer the curse for their covenant breaking (Gal. 3:13,14). Christ sent out the twelve with all authority before his ascension (cf. Matthew 28: 18-20). At the right hand of God, rules his people (Eph. 2:12-22; Col. 1:12-15; Heb. 2:14,15).
The fundamental principle of the Church is then that it is the true Israel as Paul insists (Rom. 2:28-29; 9:6; Gal. 6:16; 1 Pet. 1:1; 2:9-10; Jas. 1:1; Rom. 4:11-17; Gal. 3:7; Eph. 2:14ff; Philippians 3:3). Christ instituted a new Sanhedrin for the true Israel, a new government of his making and calling. When we consider the government of the Church therefore we must see that it will have a form continuous with that of the Old Testament. The Church was not a Jewish sect or a charismatic cult springing up separately in diverse and strange communities and forms wherever it appeared. It was nothing less than the true Israel to which all the prophets gave witness (Acts 7:38; Amos 9:11-12 cp. Acts 15:15-18; Acts 13:17; cf. Deuteronomy 7:7).
For an overview of the way in which Scripture shows that the Church is Israel now, read Charles D. Provan's booklet with that title. It is a collection of relevant Bible verses under various headings to demonstrate this truth.