(1) The usual word is `ol (Ge 27:40, etc.), less commonly the (apparently later) form moTah (Isa 58:6, etc.; in Nab 1:13 moT), which the Revised Version (British and American) in Jer 27:1-22; 28 translates "bar" (a most needless and obscuring change). The Greek in Apocrypha (Sirach 28:19, etc.) and in the New Testament (Mt 11:29 f, etc.) is invariably zugos. Egyptian monuments show a yoke that consisted of a straight bar fastened to the foreheads of the cattle at the root of the horns, and such yokes were no doubt used in Palestine also; but the more usual form was one that rested on the neck (Ge 27:40, etc.). It was provided with straight "bars" (moToth in Le 26:13; Eze 34:27) projecting downward, against which the shoulders of the oxen pressed, and it was held in position by thongs or "bonds" (moceroth in Jer 2:20; 5:5; 27:2; 30:8; 'aghuddoth in Isa 58:6, "bands"), fastened under the animals' throats. Such yokes could of course be of any weight (1Ki 12:4 ff), depending on the nature of the work to be done, but the use of "iron yokes" (De 28:48; Jer 28:13 f) must have been very rare, if, indeed, the phrase is anything more than a figure of speech.
What is meant by "the yoke on their jaws" in Ho 11:4 is quite obscure. Possibly a horse's bit is meant; possibly the phrase is a condensed form for "the yoke that prevents their feeding"; possibly the text is corrupt.
The figurative use of "yoke" in the sense of "servitude" is intensely obvious (compare especially Jer 27:1-22, Jer 28:1-17). Attention needs to be called only to La 3:27, where "disciplining sorrow" is meant, and to Jer 5:5, where the phrase is a figure for "the law of God." This last use became popular with the Jews at a later period and it is found, e.g. in Apocrypha Baruch 41:3; Psalter of Solomon 7:9; 17:32; Ab. iii.7,. and in this sense the phrase is employed. by Christ in Mt 11:29 f. "My yoke" here means "the service of God as I teach it" (the common interpretation, "the sorrows that I bear," is utterly irrelevant) and the emphasis is on "my." The contrast is not between "yoke" and "no yoke," but between "my teaching" (light yoke) and "the current scribal teaching'; (heavy yoke).
(2) "Yoke" in the sense of "a pair of oxen" is tsemedh (1Sa 11:7, etc.), or zeugos (Lu 14:19).
Burton Scott Easton