In evangelical churches, it is typical for the pastor to open the worship service with “Good morning!” or “Welcome!” or even with a joke as an “ice-breaker.”
In contrast to this man-centered opening words, Reformed worship begins with the minister reading God’s word calling his covenant people to assemble for worship. Was this Reformed practice, which has largely disappeared from evangelical worship, invented by the Reformers? No, for when Yahweh constituted Israel “in the day of the assembly” (Hebrew qahal, Greek ekklesia in Deut 18:16) as his covenant people, his “treasured possession… a kingdom of priests and a holy nation” (Exod 19:5-6), he called his people to assemble before Mount Sinai,
So Moses came and called the elders of the people and set before them all these words that the LORD had commanded him (Exod 19:7).
Forty years later, when they reached the gates of Canaan on the plains of Moab, Israel was called again by God to a covenant renewal ceremony:
And Moses summoned all Israel and said to them, “Hear, O Israel, the statutes and the rules that I speak in your hearing today, and you shall learn them and be careful to do them (Deut 5:1).
It is God who calls us to assembly; we do not assemble together of our own desire. We can only come because God invites us—indeed, he commands us—to assemble. God does not need our worship because he does not need anything in himself (Acts 17:24-25; Rom 11:34-35). On the contrary, he commands us his covenant people to worship him. As well, when the worship service is opened with the Call to Worship, we know that it is God who has the first word in the service, and we respond to his word. Later, we will also see that God also has the last word in the service: the Benediction.
God then commanded the people to consecrate themselves—setting themselves apart as holy—making themselves clean and avoiding all distractions for two days, for on the third day they were to assemble themselves before God for worship (Exod 19:10-15). This means that we as God’s chosen, holy nation (1 Pet 1:1; 2:9) are to solemnly prepare ourselves before the Lord’s Day. As a child raised in a Christian home, I remember that almost all of our Saturday evenings were spent on picking our best clothes, ironing them, shining our shoes, and making sure that we get up early the next day to go to Sunday worship services.
Do we prepare ourselves for the Lord’s Day in the manner that the Westminster divines recommend, “We are to prepare our hearts, and with such foresight, diligence, and moderation, to dispose and seasonably dispatch our worldly business, that we may be the more free and fit for the duties of that day” (Larger Catechism 117)?
If the whole of our Saturdays are preoccupied with work, shopping and leisure, how do we prepare to “hear the Word preached, [to] attend upon it with diligence, preparation, and prayer” (WLC 160)? And if these things distract us before the Lord’s Day worship, how are we to prepare for the Lord’s Supper in “examining ourselves of our being in Christ, of our sins and wants; of the truth and measure of our knowledge, faith, repentance…” (WLC 171)?
Moreover, we find many Scriptures in which God calls his congregation to assemble for public worship:
Oh come, let us sing to the LORD; let us make a joyful noise to the rock of our salvation! Let us come into his presence with thanksgiving; let us make a joyful noise to him with songs of praise! (Psa 95:1-2)
From you comes my praise in the great congregation; my vows I will perform before those who fear him (Psa 22:25).
I will thank you in the great congregation; in the mighty throng I will praise you (Psa 35:18).
I have told the glad news of deliverance in the great congregation; behold, I have not restrained my lips, as you know, O LORD. I have not hidden your deliverance within my heart; I have spoken of your faithfulness and your salvation; I have not concealed your steadfast love and your faithfulness from the great congregation (Psa 40:9-10).
I will come into your house with burnt offerings; I will perform my vows to you (Psa 66:13).
Ascribe to the LORD the glory due his name; bring an offering, and come into his courts! (Psa 96:8)
Make a joyful noise to the LORD, all the earth! Serve the LORD with gladness! Come into his presence with singing! Enter his gates with thanksgiving, and his courts with praise! Give thanks to him; bless his name! (Psa 100:2, 4)
Let them extol him in the congregation of the people, and praise him in the assembly of the elders (Psa 107:32).
Praise the Lord! I will give thanks to the Lord with my whole heart, in the company of the upright, in the congregation (Psa 111:1).
I was glad when they said to me, “Let us go to the house of the Lord!” (Psa 122:1)
Praise the LORD! Praise the name of the LORD, give praise, O servants of the LORD, who stand in the house of the LORD, in the courts of the house of our God! (Psa 135:1-2)
This ancient opening of the public worship of God therefore is rooted in Scriptures. The minister does not have to worry that he will run out of Scripture texts to call the assembly of God’s people, for he has a deeply rich mine of resources from Scriptural texts.