Acts 1:15-17, 20-26
 In those days Peter stood up among the brothers (the company of persons was in all about 120) and said,  "Brothers, the Scripture had to be fulfilled, which the Holy Spirit spoke beforehand by the mouth of David concerning Judas, who became a guide to those who arrested Jesus.  For he was numbered among us and was allotted his share in this ministry." …
 "For it is written in the Book of Psalms,
" 'May his camp become desolate,
and let there be no one to dwell in it';
" 'Let another take his office.'
 So one of the men who have accompanied us during all the time that the Lord Jesus went in and out among us,  beginning from the baptism of John until the day when he was taken up from us—one of these men must become with us a witness to his resurrection."  And they put forward two, Joseph called Barsabbas, who was also called Justus, and Matthias.  And they prayed and said, "You, Lord, who know the hearts of all, show which one of these two you have chosen  to take the place in this ministry and apostleship from which Judas turned aside to go to his own place."  And they cast lots for them, and the lot fell on Matthias, and he was numbered with the eleven apostles.
The text above is taken from the reading in Acts for the 7th Sunday of Easter (May 24, 2020). I titled my sermon for that day “Why Twelve?” We know that God used the Old Testament history as a means to show people that he was a God who could be trusted, one who always told the truth, in fact he tells things like they are. He wants us to see his plan to restore us to that perfect relationship with Himself which means that we need to know he keeps His word and that we can trust the redemptive work of his only Son, Jesus Christ who died for our sins and restores the righteousness we had in the Garden of Eden before the fall. He wants us to take comfort that we are able to be with Him in the heavenly kingdom as it arrives. We also know that God took his time to enable us to trust Him, but he also used a variety of techniques to do it. One of those techniques was the use of numbers to tell the full story of God’s plan for our redemption, so that is what I want to show with this message. Therefore, WHY TWELVE?
The number 12 appears 187 times in Scripture so we know that it was important to God. It is almost always related to government and refers to perfection or authority related to that government. The use of 12 begins with the 12 sons of Jacob who were to become the fathers of the 12 tribes of Israel. One of the things we know about God from the Garden of Eden is his desire to be always present with his people, and this becomes evident again when he gives Moses the instructions for the tabernacle. God would reside in that perfect location within the tabernacle in what was called the Holy of Holies and it had a perfect shape, a cube. Why a cube? Well it is made up of twelve sides, all precisely the same length so the cube becomes that perfect shape for God to reside with His chosen people during their 40 years in the wilderness. God further uses the number 12 while still in the wilderness by assigning three of the 12 tribes to camp on each side of the tabernacle. Even when it was time to enter the Promised Land 12 men, one from each tribe, followed the Ark of the Covenant over the Jordan river and a stone memorial of 12 stones was built on the other side.
During the ministry of Jesus, he had many disciples, we do not know how many, but we do know that there were more than 12 and that they consisted of both men and women. Twelve were appointed by Jesus to become the apostles that would become the foundation of the church. But one, Judas, betrayed Jesus and is now being replaced by one of two candidates who had been with them from the time of Jesus' baptism until his ascension qualifying them as witnesses of Jesus ministry. Notice that Luke tells us that in the room were about 120 disciples to keep the number 12 in use. I have been told by a biblical historian that if there were 12 witnesses to an event then a trial was not required. As that perfect number, 12 represents truth. Thus, when Pentecost comes, there are 12 witnesses standing before the crowd with tongues of fire on their heads proclaiming the truth of Jesus words.
But we are not finished with the story of God’s plan for salvation, so I will use some of the facts from the Book of Revelation to complete the story. In chapter 7 it is depicting the Church militant figuratively consisting of an army from each of the twelve tribes of the Old Testament using 12,000 men from each. Thus, using the multiplier 10 three times and 12 squared is 144 so this army consists of 144,000 people. But now the clincher, the New Jerusalem comes down from heaven in the shape of that perfect cube. It is 12000 stadia on each side, so it could reach from New York City to Chicago. The city has 12 gates, three on each side and they have the names of the 12 tribes just as they were surrounding the tabernacle. But there are also 12 foundations bearing the names of the 12 apostles who became the foundations of the Church on Pentecost. There were also 12 types of jewels making up the new Jerusalem.
What is different about this new city is that in the Holy of Holies of the tabernacle, only the High Priest could enter on the day of Atonement and only after he had been made pure by his sacrifices. In the New Jerusalem, all those who have been made righteous by the death and resurrection of Jesus can enter through those 12 gates. The New Jerusalem is then the restoration of that perfect relationship that existed between Adam and Eve with God in the Garden of Eden before the fall. Jesus has fulfilled the promises of the Old Testament and we now know that we can fully trust God using the numbers he uses in Scripture.