THE WORD SELAH Does not have a clear meaning today. I who pray in Hebrew understood it all my life as resembling the amen, that is, that it be so or blessed. (It's what I remember my mother explaining to me that she was a philologist and spoke Hebrew and 13 other languages). But as almost every time it comes out at the end of the verses in the psalms, which were sung, it seems that it was a musical notation, of which there are many in the scrolls, as an aid to the singer who reads in the tabernacle.