This psalm initially expressed the delight of worshippers as they arrived in Jerusalem for one of the annual feasts. It contains several important lessons regarding public worship.
First, there is in verse 1 mutual exhortation to worship. It is important for us to encourage one another as we go to meet with God. In his presence, we regain a proper perspective on life and are released from the competing pressures that influence us adversely on a daily basis.
Second, verses 1 and 2 also highlight the wonderful reality of sharing public worship with those whom God has rescued from spiritual danger. When the worshippers stepped within the city gates they found themselves within a secure environment. The city was surrounded with walls, which gave protection to the inhabitants. Similarly, public worship is a reminder of the security of God’s people, that they have been delivered from their sins and are no longer under the judgement of God.
Third, entering Jerusalem gave pilgrims the opportunity of observing the buildings of the city (v. 3). The psalm indicates that it was a well-designed city. The same is true of the spiritual Jerusalem, whether we think of it in its heavenly location or its earthly expression in the visible church. An obvious feature of the literal city was its ability to cater for the vast numbers that gathered for the annual feasts. Similarly, the church of Christ has enough room for all who wish to join it. Of course, the room is for those who want to worship God, to think about his salvation.
Fourthly, in verse 4, the psalm mentions the unity of the people. Whatever their background, social level, intellectual abilities, or age, they were together. The place where unity is shown on a weekly basis is the local congregation.
Fifthly, again in verse 4, the psalmist draws attention to the twofold purpose of gathering in Jerusalem. One was to listen at Israel’s testimony (the place where the priests instructed the people about God and his purposes) and the other was to give thanks to God. Public worship is a two-way event, an interaction between God and those who worship. There has to be instruction by those whom God has gifted for this role; there has to be a response from the congregation, that of thanksgiving to God for his faithfulness.
Sixthly, the psalmist mentions the importance of prayer in verses 6 and 7. Prayer is to be made for two details: peace and prosperity. It is easy to see that without peace there can be no prosperity. It has been observed that the psalmist prays for peace within the walls, not for the erection of more walls.
Seventhly, the psalmist highlights the need of personal dedication (vv. 8-9). He devotes himself to saying and doing only the things that make for peace. As far as his fellow-worshippers are concerned, his speech will focus on peaceful words, with the aim of giving to them a spirit of contentment and concord. Similarly, his actions would always have the aim of the prosperity of God’s kingdom.
Why this emphasis on peace? Because Jerusalem (Salem) is ‘the city of peace’ where the Prince of peace reigns, where the peace of God rules in the hearts of the inhabitants because they are reconciled to him.