Some Christian congregations have embraced the use of banners and flags as part of their worship services. Many of the same groups also are enthralled by shofar. And in some cases, they use them together.
This makes sense, as flags and blasts of a horn are each used as signals. it is written:
Lift up a banner in the land! Blow the shofar among the nations!The same concept is express in the Amidah prayer:
Sound the shofar throughout the land!… Raise the banner to go to Zion! Jeremiah 4:5-6
“Sound the great shofar for our freedom, raise the banner to gather our exiles and gather us together from the four corners of the earth.”I don't expect Jews to start waving banners during shofar sounding on Rosh Hashanah. Such a visual display could distract from the focus on hearing shofar. Yet on other shofar blowing occasions -- why not!
Photo from: www.worshipbanners.org/shofar_horns.php, 2012-Feb-24