to melt or dissolve: to lose all firmness and give way, whether solid ground turning to liquid or a person's courage draining away
TranslatabilityApproximateCertaintyStrong
At its core this verb pictures something solid giving way and turning to liquid. The same image runs through every use, whether what dissolves is the ground underfoot or the nerve inside a person.
Three settings recur:
The earth itself dissolves when God draws near or moves in judgment, mountains and land losing their firmness the way wax loses shape near a fire.
People melt away, their courage draining until they can no longer stand and fight. This is the word's most frequent use, the stock picture of a population that hears the news and simply comes undone with dread.
Something is actively softened or dissolved by an outside force, as rain loosens hard ground or as God wastes a person away.
Because the picture stays so physical, the emotional uses keep their force: a heart that "melts" is not merely sad but structurally undone, the way a hillside slumps and slides in a flood. The near-synonym מָסַס covers much of the same range, especially the melting of a frightened heart.
Nuances
1a(of the earth, land, or mountains) to melt and dissolve, losing all firmness, above all when God draws near or acts in judgment
the underlying picture is not tiredness but dissolving, a firm thing coming apartEzk 21:15
Both
both describe courage failing so badly that a person can no longer stand firmJos 2:24
Only faint
English "faint" suggests losing consciousness or growing weak, missing the image of melting into formlessness
“dissolve”
Comparison data is not available for this English gloss yet.
“melt away”
Comparison data is not available for this English gloss yet.
How mug differs from similar Hebrew words
מָסַסThe closest match, and the more common verb for a heart that melts in fear. This word overlaps it heavily but reaches further, into the physical dissolving of land and mountains.
רָכַךְTo grow soft or tender, which can be a good thing, as in a humbled and responsive heart. This word is softening as collapse: something once firm coming undone.
mug in the other biblical languages
τήκωGreek“to melt”The Greek verb for melting, used of the physical world dissolving, as when the elements melt with fierce heat. It shares the concrete picture but not the frequent idiom of courage draining away.
What scholars say about mug
The verb מוג denotes melting or dissolving and appears in the qal, niphal, piel, and hithpolel stems, the sense shifting in voice and intensity rather than in core meaning (HALOT; BDB). Its dominant idiomatic use is the melting of the heart or of a population in terror, a stock motif of holy-war and judgment texts (Exodus 15:15;Joshua 2:9, 24), running closely parallel to מסס (compare Joshua 2:11) and regularly tied to the collapse of courage before God's advance. A second cluster applies the verb to the created order, mountains and land dissolving at the theophany or under judgment (Amos 9:5;Nahum 1:5;Psalm 46:6). Standard lexica treat these as one polysemous root rather than separate homonyms, the figurative uses being extensions of the concrete image. TWOT and TDOT note the semantic overlap with מסס and רכך and the near-formulaic character of the fear idiom in the conquest narratives.