We may all know a family that has adopted a child. In most cases, sooner or later adopted children will learn that they were adopted. Because of their adoption, they end up with two sets of roots. They will have the roots of their adopted family and their birth family. Many adopted children often become curious about their birth family and try to learn something about them.

This having two sets of roots is also true for Christians. Christians are people who have been adopted into the family of God. In the letter to the Galatians, Paul stated,

'You are all sons of God through faith in Jesus Christ.' A little further he wrote that the Lord Jesus Christ redeemed us 'that we might receive the full rights of sons.'Gal 3:26; 4:5

This is not the full extent of the picture, however. Paul also wrote that "if you belong to Christ, then you are Abraham's seed, and heirs according to the promise" (Gal 3:29). In his letter to the Ephesians he wrote to those who were Gentiles by birth, "...remember that at that time you were separate from Christ, excluded from citizenship in Israel and foreigners to the covenants of the promise, without hope and without God in the world" (Eph 2:12). A little further in that same passage he wrote,

Consequently, you are no longer foreigners and aliens, but fellow citizens with God's people and members of God's household...Eph 2:19

It is worthwhile to reflect on the how and when of this adoption aspect of our roots as Christians. It will help us understand some aspects of the life of the church. It will also give reason for thankfulness and humility.

The Rock in the Pond⤒🔗

To understand how we have become part of God's family, considering that most do not have Jewish roots, it is helpful to think of an activity many will have done as children, namely, throw a rock into a pond or stream. When the rock hits the water, the immediate effect is that of waves rippling out in concentric circles. If the rock enters the water fairly close to the shore, the effect will be more like semi-circles. It is interesting, depending on the size of the rock, that the waves can still be seen moving out while the centre has become calm again.

This well describes the spread of the Christian faith in history. In the case of the Christian faith, it is more like a rock being thrown close to shore. It began in Jerusalem, with the ripples of the gospel message steadily moving westward. To be sure, there were some eastward ripples, even into the western part of China (sixth-tenth century), but they were feeble and never were more than a tiny presence before they faded out.

True to the image of the rock in the pond, the waves of the gospel have kept on moving outward while the place it began has calmed down. The areas first affected by the gospel only have traces remaining while new areas are experiencing the ripples dramatically for the first time. We see this in the way the gospel is receiving an audience in parts of Asia while areas like the Middle East and Western Europe, once centres of Christianity, are abandoning their Christian roots.

Three Ripples: Judea, Samaria, the Ends of the Earth←⤒🔗

This pattern was foretold in Scripture. Of course there are the many promises of the gospel going to the nations (e.g., Gen 12:3). Our Lord commanded it when he commissioned his disciples (Matt 28:18-20). The particular pattern, however, was foretold by our Lord Jesus just before he ascended.

We read about this in Acts 1:8. The Lord Jesus told his disciples, "But you will receive power when the Holy Spirit comes on you; and you will be my witnesses in Jerusalem, and in all Judea and Samaria, to the ends of the earth." This process began when the Holy Spirit was poured out on Pentecost. The new, international character of the church became evident on the day of Pentecost in the way many were able to hear about the Lord Jesus in their own language (Acts 2:1-13). The message would radiate out from Jerusalem.

In the book of Acts we see the beginning of the ripple effect of the gospel. We see this in the way the book begins with the disciples in Jerusalem and concludes with the Apostle Paul in Rome. The book of Acts can be summed up as, "From Jerusalem to Rome." In the process we can note three ripples.

First, the gospel went from Jerusalem to Judea. This was the least dramatic ripple, for it simply indicates how the gospel spread among the Jews. At the same time, however, we should not underestimate the impact for the Jews who confessed faith in Jesus. Confessing Jesus as Lord was seen as abandoning the Jewish faith. It led to rejection by the Jewish community.

Second, the gospel went to the Samaritans. The Samaritans had settled in the land after the exile of the Northern tribes around 722 BC. There was animosity between Jews and Samaritans. We learn from Acts 8 how persecution drove many believers away from Jerusalem. One of the results was that Philip preached the gospel to the Samaritans and many believed. Their inclusion was confirmed by a special outpouring of the Spirit.

The third, and most dramatic ripple, occurred when the gospel was preached to the Gentiles, a term used to describe all races that were not Jewish. In Acts 10 and 11, we learn how the Lord used a vision to impress upon Peter that the gospel should be preached to the Gentiles too. Peter ended up at the house of a Roman centurion called Cornelius. Again, the inclusion of the Gentiles was confirmed by an outpouring of the Spirit.

In Acts 11:20 we learn that it was in the church at Antioch that people began to speak to the Greeks, telling them the good news about the Lord Jesus. The church at Antioch ended up sending out Paul and Barnabas to preach the gospel to the Gentiles. The rest of the book of Acts is an account of Paul's journeys, his eventual imprisonment, and his journey to Rome. In Rome, though a prisoner, he was able to preach the gospel freely.

Rippling beyond Rome←⤒🔗

The book of Acts concludes in Rome. The waves of the gospel continued to ripple outward. The gospel slowly washed over Western Europe. It is interesting, for example, to note that it washed over England before it washed over The Netherlands. In fact, The Netherlands seemed to catch a backwash from England as missionaries from England finally succeeded in bringing the gospel to The Netherlands near the end of the seventh century. In general, however, the movement was, and is, westward. The activity is on the western edge of the wave, while areas behind the wave grow calm in the sense of becoming indifferent to the gospel.

Significant Developments at the Start of the Third Ripple←⤒🔗

This third ripple is the most significant in the way it became clear Jesus is the Saviour of the world. To be sure, there were many Old Testament promises about the adoption of people from all nations into Israel. Further, the Lord Jesus had spoken about people coming from east and west and sitting at table with Abraham. The book of Acts shows, however, that it was a difficult concept for the early church to accept. The Lord gave Peter a special vision before he received the invitation to come to the house of Cornelius. It required a special meeting in Jerusalem to discuss whether the Gentile Christians had to keep the Law of Moses (Acts 15).

The Spirit prevailed upon the church to make it clear that the church was the new Israel, without having to keep all the laws of the old Israel. The church was rooted in Jewish culture but it was not dependent upon Jewish culture. Gentile Christians did not have to adopt Jewish customs. The gospel was able to flourish and function in a Greek culture without needing to either compromise its message or destroy the culture.

A Defining Moment: the Fall of Jerusalem←⤒🔗

A defining moment in this process of the adoption of the nations into Israel was an event not mentioned in the Scriptures, namely, the fall of Jerusalem in the year 70 AD. The fall of Jerusalem was the final outcome of a Jewish rebellion against the Romans. The city and the temple were destroyed. The Lord Jesus had prophesied that this would take place (Matt 24:15-25). The believers living in Jerusalem and Judea fled to the area across the Jordan River called the Decapolis (region of ten cities), especially the city of Pella.

This event was significant for a number of reasons. First, it led to a clear separation of the Christian church from Judaism. At first, the Romans had looked upon the Christians as a Jewish sect (Acts 24:5; 14; 28:22). Now it was clear that Christianity was distinct from Judaism.

Second, it freed the church from attachment to Jerusalem and the temple. Jewish believers often still participated in the Old Testament ceremonial laws as performed in the temple. For example, Paul still went to the temple in accordance with the rules for purification (Acts 21:26). As long as the temple was there, the Christians of Gentile background would be reminded all the more of their adoption into Israel. The fall of Jerusalem put a definitive end to the involvement of Christians in rituals from the age of the shadows.

Third, the fall of Jerusalem also proved decisive in the shift to the Sunday as the day for Christian worship. Especially the early Jewish Christians had still honoured the Sabbath day. Sabbath keeping was one of the marks of the Jews. Worshipping on the Sunday set the Christians apart from the Jews. As the Christians distanced themselves from the Jewish rebellion, the church began to develop fully as a separate institution also in the eyes of the Roman authorities.

Being Thankful and Careful←⤒🔗

We began by speaking about being adopted children in God's family. It is popular in our age to speak about the time of one's personal adoption, that is, one's personal coming to faith. Ironically, that approach suggests the child decides to be adopted, in contrast to the process of adoption where the parents are active and the children passive. When we look at our roots, there will be different individual stories of how the gospel has come to us. While not denying the individual ways the Lord has used to draw us into the household of God, the true Israel, we should have an eye for the bigger picture, of how God in his grace has adopted those who were not his people and made them his people. This whole process was set in motion at Pentecost and continues to work itself out in the present.

Our individual adoption as children of God plays itself out within that larger process of adoption.

The fact that we are adopted into Israel is important for it shows us our Old Testament roots. It means that Israel's history has become our history. Some of the events at the third ripple, where the gospel went to the nations, also are critical for understanding how to work with that part of our spiritual family history, the Old Testament Scriptures. It is reason for thankfulness that we have been adopted.

At the same time, the awareness of how the water has quieted down while the ripple moves westward should also caution us. Paul warned the Romans that those grafted into Israel through faith would be cut off if they fell into unbelief (Rom 11:17-21). The Lord Jesus also warned the church at Ephesus that he could move their lampstand elsewhere (Rev 2:5).

In the end, knowing about our adoption should make us both thankful and careful.