Coal
COAL. Often found in the English Bible, the word never refers to true mineral coal, which has not been found in Palestine proper, where the geological formation as a whole is recent. Coal of a poor quality has been found at Sidon, and for a time some was mined in Lebanon. The half dozen Hebrew and Greek words rendered “coal” refer either to charcoal or to live embers of any kind. Charcoal was used by the Hebrews to provide warmth in winter (Isa.47.14; John.18.18), for cooking (Isa.44.19; John.21.9), and for blacksmith work (Isa.44.12; Isa.54.16). It was made by covering a carefully stacked pile of wood with leaves and earth, and then setting fire to it. After several days of burning and smoldering, the wood was converted into charcoal and the pile was opened.
In Ps.120.4 there is mention of “coals of the broom tree.” In 1Kgs.19.6 and Isa.6.6 the Hebrew word denotes a hot stone. Frequently the word is used metaphorically, as in Prov.26.21 (niv “charcoal”). In Prov.25.22 and Rom.12.20, where we are told to give to an enemy good in return for evil, thus heaping coals of fire on his head, the coals of fire are not meant to suggest the pain of punishment to the guilty but the softening of his heart as he thinks with burning shame of his unworthy hatred. Love will melt and purify. In Lam.4.8 the literal meaning of the Hebrew word translated “coal” by KJV, “soot” by NIV and RSV, is “blackness.”——SB
COAL, COALS. The term primarily refers to charcoal, since Pal. does not have deposits of mineral coal. Mainly two Heb. words designate charcoal.
2. פֶּחָם, H7073, LXX, ἄνθραξ, G472, appears at least three times in the OT. Twice it designates burning charcoal in a forge (Isa 44:12; 54:16) and once unburnt charcoal (Prov 26:21). Its meaning in Psalm 11:6 is problematical.
The following words are tr. in KJV as coal or coals, but most others are not.
3. רֶ֫שֶׁף, H8404, LXX πυ̂ρός is so rendered in Song of Solomon, but the term does not refer to charcoal. It is a hot stone.
4. רִצְפָּה, H8365, LXX, ἄνθραξ, G472, is found in 1 Kings 19:6 and Isaiah 6:6 but seems to designate hot stones rather than live charcoal.
5. שְׁחוֹר, H8818, LXX, ἀσβόλος would be better tr. as blackness instead of coal (Lam 4:8).
International Standard Bible Encyclopedia (1915)
In Ps 120:4, there is mention of "coals of juniper," the Revised Version, margin "broom," rothem. This is doubtless the Arabic retem, Retama roetam, Forsk., a kind of broom which is abundant in Judea and Moab. Charcoal from oak wood, especially Quercus coccifera, L., Arabic sindyan, is much preferred to other kinds, and fetches a higher price.
In most of the passages where English versions have "coal," the reference is not necessarily to charcoal, but may be to coals of burning wood. Pecham in Pr 26:21, however, seems to stand for charcoal: "As coals are to hot embers, and wood to fire, So is a contentious man to inflame strife." The same may be true of pecham in Isa 44:12 and Isa 54:16; also of shechor in La 4:8.