"important feature in education, and should not be neglected. Singing, as a part of religious service, is as much an act of worship as is prayer. The heart must feel the spirit of the song, to give it right expression. CE 62.4"
"Serve the Lord with gladness: come before his presence with singing."
EGW's statement that singing is an act of worship aligns with the principle expressed in Psalm 100:2, which encourages serving the Lord with gladness and singing. EGW expands on the idea by emphasizing the importance of feeling the spirit of the song.