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Fuller
Fuller [EBD]
The word "full" is from the Anglo-Saxon fullian, meaning "to whiten." To full is to press or scour cloth in a mill. This art is one of great antiquity. Mention is made of "fuller's soap" (Mal. 3:2), and of "the fuller's field" (2 Kings 18:17). At his transfiguration our Lord's rainment is said to have been white "so as no fuller on earth could white them" (Mark 9:3). En-rogel (q.v.), meaning literally "foot-fountain," has been interpreted as the "fuller's fountain," because there the fullers trod the cloth with their feet.
FULLER [SMITH]
The trade of the fullers, so far as it is mentioned in Scripture, appears to have consisted chiefly in cleansing garments and whitening them. The process of fulling or cleansing clothes consisted in treading or stamping on the garments with the feet or with bats in tubs of water, in which some alkaline substance answering the purpose of soap had been dissolved. The substances used for this purpose which are mentioned in Scripture are natron, (Proverbs 25:20; Jeremiah 2:22) and soap. (Malachi 3:2) Other substances also are mentioned as being employed in cleansing, which, together with alkali, seem to identify the Jewish with the Roman process, as urine and chalk. The process of whitening garments was performed by rubbing into them calk or earth of some kind. Creta cimolia (cimolite) was probably the earth most frequently used. The trade of the fullers, as causing offensive smells, and also as requiring space for drying clothes, appears to have been carried on at Jerusalem outside the city.FULLER [ISBE]
FULLER - fool'-er (kabhac; literally, "to trample," gnapheus): The fuller was usually the dyer, since, before the woven cloth could be properly dyed, it must be freed from the oily and gummy substances naturally found on the raw fiber. Many different substances were in ancient times used for cleansing. Among them were white clay, putrid urine, and the ashes of certain desert plants (Arabic qali, Biblical "soap"; Mal 3:2). The fuller's shop was usually outside the city (2 Ki 18:17; Isa 7:3; 36:2), first, that he might have sufficient room to spread out his cloth for drying and sunning, and second, because of the offensive odors sometimes produced by his processes. The Syrian indigo dyer still uses a cleaning process closely allied to that pictured on the Egyptian monuments. The unbleached cotton is soaked in water and then sprinkled with the powdered ashes of the ishnan, locally called qali, and then beaten in heaps on a flat stone either with another stone or with a large wooden paddle. The cloth is washed free from the alkali by small boys treading on it in a running stream or in many changes of clean water (compare En-rogel, literally, "foot fountain," but translated also "fuller's fountain" because of the fullers' method of washing their cloth). Mark describes Jesus' garments at the time of His transfiguration as being whiter than any fuller on earth could whiten them (Mk 9:3).James A. Patch
Also see definition of "Fuller" in Word Study