Acts 2:41-42 says, “Those who received His Word were baptized, and there were added that day about three thousand souls. And they devoted themselves to the apostles' teaching and fellowship, to the breaking of bread and the prayers.”
This text shows that the New Testament church devoted itself to certain basic activities. Churches are free to do all kinds of good things, but they must never neglect what is most basic. Historically, these basic things have been called the "primary means of grace," because they are the first means the church must diligently employ. They have also been called the "ordinary means of grace" because they are "ordained" or "instituted" by Christ. The means of grace only sanctify the church and advance the kingdom when appropriated by faith.
The Baptist Catechism says:
Q 93. What are the outward means whereby Christ communicateth to us the benefits of redemption?
A. The outward and ordinary means whereby Christ communicateth to us the benefits of redemption are his ordinances, especially the word, baptism, the Lord's supper, and prayer; all which means are made effectual to the elect for salvation (Mt. 28:19, 20; Acts 2:42, 46, 47).
Devoted to the Apostles' Teaching
The Apostles' teaching is deposited in the Bible. The Bible should be read, sung, and publicly preached in corporate worship services on the Lord's Day. God calls His people to faithfully attend public worship to exalt the risen Savior, to be equipped to live in daily fellowship with Christ, to be taught to think rightly about Him, and to live all of life according to His gracious gospel. God's people must not neglect “to meet together as is the habit of some” (Heb 10:25).
Devoted to Fellowship
Fellowship with the saints means knowing one another in Christ, bearing one another's burdens, and encouraging and exhorting one another in holy living. It is not enough to attend public worship without building solid and edifying relationships with other Christians. We need to know each other in Christ to be healthy Christians. Christian fellowship is a means by which the church is strengthened to fellowship with Christ.
Devoted to Baptism
The text doesn't explicitly say they were "devoted" to baptism, but the mention of baptism in verse 41, implies that they certainly were. The church only baptized those who "received His Word," or professed belief in the message preached. These baptized Christians were subsequently "added." To what were they added? They were added to the number of those counted as belonging to the visible church. The fact that the converts were baptized and numbered implies that there was a well-defined local assembly and an accounting for who was a member of the church and who was not.
Devoted to the Breaking of Bread
The "breaking of bread" denotes the Lord's Supper (1 Cor 10:16). The Lord's Supper is a church ordinance, which Christ commanded His church to observe together to strengthen its corporate faith and unity as it remembers the sacrifice of Christ, its union with Him, and its call to die to sin and live as Christ lived. The Lord's Supper is not an empty ceremony. It is a vital memorial meal, and a faith strengthening ordinance for the church, which God said to observe until Christ returns (1 Cor 11:26). Scripture says that faithfully taking the Lord's Supper with the church of the Lord Jesus is an act of communion with Christ (1 Cor 10:16-17).
Devoted to Prayers
The New Testament churches devoted themselves to corporate prayer. Private prayer is important (Matt 6:6), but so is praying together as a church (Acts 4:24-31; 12:5, 12). Scripture shows how God works mightily through the prayers of His people assembled. Our personal and corporate devotion to Christ is strengthened by corporate prayer. Charles Spurgeon, the great English Baptist preacher of the 19th Century, said that the secret of the power of preaching and the advancement of the gospel in his time was the praying church.