"Singing with grace in your hearts"
Our singing is done by the whole congregation and without instrumental accompaniment, called acappella singing.
We do it that way because it replicates the manner it was done in the first century church. Our singing offers the "sacrifice of praise, the fruit of our lips" in worship and thanksgiving to God. We sing with one another songs of instruction, encouragement and praise to God.
"Let the word of Christ dwell in you richly in all wisdom, teaching and admonishing one another in psalms and hymns and spiritual songs, singing with grace in your hearts to the Lord."
"Therefore by Him let us continually offer the sacrifice of praise to God, that is, the fruit of our lips, giving thanks to His name."