The short, technical answer is: Never--at least among people who claim, as Western Evangelical Christians do, to hold the Bible to be the inspired Word of God and to teach how a believer in Jesus should live.
In the New Testament, the church is an assembly of people and the Church of God is an assembly of the people of God (who are followers of Jesus Christ). In the New Testament, the church is not a destination. It is not a thing that can be gone to.
As Jesus says, the church is present when even two or three are gathered in his name. (Mt. 18:17-20)
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The New Testament Greek word is
egkataleipo.
That word appears 10 times in the New Testament. Half of those appearances are New Testament quotations of the Old Testament: Mt. 27:46, Mk. 15:34, Acts 2:27, Rom. 9:29, Heb. 13:5.
Of the others,
egkataleipo appears in Peter's address to the crowd on Pentecost, in Paul's accounting of hardships he had encountered in his ministry in 2 Corinthians 4, twice when Paul is relating ill treatment by coworkers during his imprisonment (see 2 Tim. 4) and it appears in Hebrews 10.
Egkataleipo is the Greek word used to translate Jesus' quotation of Psalm 22:1 from the cross when He cried out, "My God, my God, why have you
forsaken me?" It's the word Peter uses on Pentecost to quote David saying, "...you will not
abandon my soul..." It is Paul's word to the Corinthians when he said, "We are hard pressed on every side,
but not crushed; perplexed,
but not in despair;
persecuted, but not abandoned; struck down, but not destroyed."
Egkataleipo means to abandon, to leave, to desert, to forsake, to neglect.
And, it is the verb used, in the negative, (i.e., preceded by the word "not") to define the frequency with which disciples should be attending what we are now calling--without New Testament authority--a "worship service."
And let us consider how to stir up one another to love and good works, not neglecting to meet together, as is the habit of some, but encouraging one another. . .. (Heb. 10:24-25, ESV)
The "not neglecting" part is the part with
egkataleipo in it.
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The fact is that Jesus never commanded His disciples anything that even remotely resembles, "go to church." He never spoke of such a phenomenon as a "worship service." These concepts are foreign to Him, and to the lives of early followers of the Way.
While there are some references in the Book of Acts to the gathering together of believers, there isn't much mention of that activity among early believers. Acts 2 says that that they met every day in the temple courts and broke bread in their homes. Acts 20 contains the Book of Acts' only description of a gathering of disciples when "on the first day of the week...we gathered together to break bread." (This is the story where Paul drones on and on and the kid falls asleep and tumbles out the window.) But, in Acts, that's just about it for disciples "going to church" in any way.
Apart from the Gospels and Acts: In most of Paul's letters there is no discussion at all of the gathering together of saints. There is that important lengthy passage from 1 Cor. 11-14, where Paul discusses it in detail and chapter 5 in which he gives direction about what the Corinthians should do when they would gather to deal with an issue of immorality of one member of their gathering, when they would meet to, “Expel the wicked person from among you.”
Occasionally, Paul also mentions a church that meets at someone's house. But other than that? Nothing.
The letters of Peter and John are not concerned with what goes on when people gather as followers of Jesus. James 2:2-4 makes a passing reference but just that.
Considering the example and the teaching of the New Testament, what we today call "going to church" or attending a "worship service" was barely a blip on the radar among the important components of the lifestyle of early disciples of Jesus. It certainly was not central to the lifestyle of those followers of the Way.
Tragically, today, the community of Jesus-followers--especially in the West--are all about going to church and attending the worship service in a way that has no authority or precedent in the Word of God.
This is one of many instances in which the twenty-first century Western church defines righteousness in a way that is false and entirely disconnected from the teaching of the Lord of the church and the example of Jesus and his first disciples.
In fact, comparing the twenty-first century Western Christian community with the one presented in the New Testament, it seems very fair to say that today's community is guilty of a dangerous form of unrighteousness: The sin of
ecclesiolatry--the veneration of church in place of the worship of God.
Today's Western Christians are unrighteously consumed with the church.
They think of obedience to the command of Jesus to go into the world making disciples as, essentially, a simple injunction to start new churches. Many denominations have been defining, as a key indicator of success on mission, the increase in the number of churches under their authority. Therefore, they plant churches and they adopt churches and they renew churches.
None of those activities are contained in the record of the early Christians in the New Testament.
Early Christians used several words the describe the manner is which they proclaimed the gospel. Their goal was never to start a new church or to expand the church. The goal always was to bring
people to repentance and to belief in the good news that Jesus Christ "died for our sins according to the Scripture, that He was buried, that He was raised on the third day according to the Scriptures and that He was seen by Peter (and others)."
Early Christians were focused on making disciples. Today's ecclesiolaters--worshippers of church, not the Lord of the church--are content to create churches.
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So, how often should followers of Jesus go to church? Attend a worship service?
Even using a definition of the gathering together consistent with the New Testament example, the Word's answer to the question is that they shouldn't
neglect meeting together; they shouldn't
abandon that activity or
forsake it. That is the New Testament's strongest endorsement.
There are, according to the Word, aspects of being a disciple far more important than attending a gathering. These are the components of discipleship will be considered when people's lives are judged for eternity. According to Jesus and the apostles, the going, or not going, to church will not even be considered at that moment.
According to Jesus, living lives of justice and mercy and faithfulness (Mt. 23) and the care of individuals among the least of His brothers and sisters (Mt. 25) will be considered.
According to Paul, doing the good works that are the product of faith in Jesus (Eph. 2:8-10) is essential.
In fact, according to Heb. 10, the purpose of gathering seems to be that disciples would stir each other up to the love and good works that Jesus and Paul preached were the essence of the life of those who love Him.
The truth is that the 'How often' question is a question that is out of sync with what Jesus and early Christians taught and did. Dangerously, it is a vital question among today's Western Christians.
Better questions, from a New Testament perspective, are:
- Why gather together with other disciples at all, and,
- What is the goal of the gathering together of disciples?
The answers of today's Western Christians are poor answers--based on the practice of Jesus and His disciples.
Is this a true statement?
Today, attending church is the central act of righteousness for someone who has "accepted" Christ.
In my opinion, it is true.
Because of that, attending church is, today, an end unto itself.
This is why, today, church leaders find it important to count "worship attendance" and why our New Testament brothers and sisters never once counted the number of people who gathered together.
Among early Christians, gathering together with other believers was a means to the end of possessing a genuine faith that produced acts of righteousness. These days, attending church is, itself, an act of righteousness.
It is, unbiblically, a measure of a church's success.