Just a few additional thoughts as it relates to the connection between music and liturgy, and the song selection process.
When selecting hymns, be encouraged to find quiet moments so that you can feel the impulses of the Holy Spirit. This opens the opportunity for Him to guide our thoughts, and helps us to find a contentedness in our hymn selections. As Jesus taught us, “Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you.” (Matthew 7:7)
All song selections need to be about God, and thus sacred in nature. Secular songs do not have a place in the divine service experience, nor do patriotic songs (the latter should be reserved for concerts or more casual gatherings, such as outdoor fellowships). Classical pieces can be used when they are fitting for the moment, as many were originally written for church use (although discernment is still encouraged). All of the musical selections within the experience should be focusing our thoughts on God the Father, Son, and Holy Spirit.
Note that soloists, instrumentalists, and small groups should stand to the side when singing or playing. Always remember that we are not performing, but rather making an expression to God. Worship is always the aim, and the glorification of God the goal.
Where possible, it may be beneficial to select songs in advance of each month. This way, everyone on the worship and music team knows the plan for the month, and directors and accompanists have plenty of time to rehearse and prepare. Having the songs selected in advance of each month is also helpful when it comes to knowing which selections need to be rehearsed. Rehearsals—which are important, and should be taking place—become more intentional and purposeful this way.
Lastly—for different Christian holidays, seasonal songs are not the exceptions to the music and liturgy guidelines that have been outlined. A Christmas or Easter song still has to fit in the liturgical moment of the
divine service experience. No matter the season, always consider the characteristics of the song, the placement of it, and the flow and connection between liturgy and music.
I hope that you find these thoughts, and the teachings on liturgy and music, to be useful in your work of ministry, and as you serve Christ and your congregation.