dum (alam, 'illem, literally, "tied in the tongue"; kophos): Used either as expressing the physical condition of speechlessness, generally associated with deafness, or figuratively as meaning the silence produced by the weight of God's judgments (Ps 39:2-9; Da 10:15) or the oppression of external calamity (Ps 38:13). As an adjective it is used to characterize inefficient teachers destitute of spirituality ("dumb dogs," Isa 56:10). The speechlessness of Saul's companions (Ac 9:7) was due to fright; that of the man without the wedding garment was because he had no excuse to give (Mt 22:12). Idols are called mute, because helpless and voiceless (Hab 2:18-19; 1Co 12:2). The dumbness of the sheep before the shearer is a token of submission (Isa 53:7; Ac 8:32).
Temporary dumbness was inflicted as a sign upon Ezekiel (3:26; 24:27; 33:22) and as a punishment for unbelief upon Zacharias (Lu 1:22). There are several cases recorded of our Lord's healing the dumb (Mt 15:30; Mr 7:37; Lu 11:14, etc.). Dumbness is often associated with imbecility and was therefore regarded as due to demoniac possession (Mt 9:32; 12:22). The evangelists therefore describe the healing of these as effected by the casting out of demons. This is especially noted in the case of the epileptic boy (Mr 9:17). The deaf man with the impediment in his speech (Mr 7:32) is said to have been cured by loosening the string of his tongue. This does not necessarily mean that he was tongue-tied, which is a condition causing lisping, not stammering; he was probably one of those deaf persons who produce babbling, incoherent and meaningless sounds. I saw in the asylum in Jerusalem a child born blind and deaf, who though dumb, produced inarticulate noises.
In an old 14th-century psalter "dumb" is used as a verb in Ps 39:1-13: "I doumbed and meked and was ful stille."