The Hebrew word lashon refers primarily to the tongue as the physical organ of speech, and by extension to language, speech, and even the shape of a tongue (as in a tongue of fire or a tongue of land). It appears over 115 times in the Old Testament. The tongue is central to blessing and cursing, to truth and deception, to praise and slander. It is a small member with enormous power — a theme developed at length in Proverbs and echoed by James in the New Testament (James 3:5–6).
The lashon is the instrument of covenant faithfulness or covenant breaking. The Psalmist consecrates his tongue to praise: My tongue will tell of your righteous acts all day long (Psalm 71:24). Proverbs warns of the destructive tongue: The tongue has the power of life and death (Proverbs 18:21). Isaiah's cleansing was centered on his lips (Isaiah 6:7). At Pentecost, God reversed Babel — tongues of flame enabled every nation to hear God's glory in their own lashon (Acts 2). One day, every tongue will confess that Jesus Christ is Lord (Philippians 2:11).