That word signaled the musicians to do one of two things: play more loudly or play on alone while the singers stop.
I can feature the singers stopping when they got to the end of this verse:
“I acknowledged my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the LORD; and thou forgavest the iniquity of my sin. Selah.” (Psalm 32:5).
The song wasn’t over but this was such a tremendous truth that the singing itself stopped so people could give focused thought on what they had just heard.
I won’t try to hide my sin and wrongdoing. I will say to God, “I did it. I’m sorry. Please forgive me. And help me not to do it again.”
Then God forgives! Wow!
Selah for sure — be sure you think about that, Mark.
Now you may continue singing.