According to the author of 1 Chronicles, this verse is about a group of people named Zechariah, Aziel, Shemiramoth, Jehiel, Unni, Eliab, Maaseiah, and Benaiah, who played music on special instruments called psalteries. They were using these instruments for a happy and important celebration.
1 Chronicles 15:20: And Zechariah, and Aziel, and Shemiramoth, and Jehiel, and Unni, and Eliab, and Maaseiah, and Benaiah, with psalteries on Alamoth;
This verse encourages speaking to one another in psalms, hymns, and spiritual songs, contrasting the organized use of psalteries directed for musicians in 1 Chronicles 15:20, suggesting a more spontaneous expression of worship.
Ephesians 5:19: Speaking to yourselves in psalms and hymns and spiritual songs, singing and making melody in your heart to the Lord;