Numbers 10:8-9

8 aAnd the sons of Aaron, the priests, shall blow the trumpets. The trumpets shall be to you for a perpetual statute throughout your generations. 9And bwhen you go to war in your land against the adversary who coppresses you, then you shall dsound an alarm with the trumpets, that you may be eremembered before the Lord your God, and you shall be saved from your enemies.
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