though trembling cannot be well ascribed to them, they being so fixed to the backbone: rather therefore, as Aben Ezra, the hands and arms are meant; which work for the maintenance of the body, and feed it with food, got and prepared by them; and which protect and defend it from injuries; for all which they are fitted, and made strong by the God of nature.
The Arabic version renders it, "both keepers"; and, doubtless, respects both hands and arms; and which, in old age, are not only wrinkled, contracted, and stiff, but attended with numbness, pains, and tremor.
Some, not amiss, take in the head; which is placed as a watchtower over the body, the seat of the senses; which overlooks, guards, and keeps it, and which often through paralytic disorders, and even the weakness of old age, is attended with a shaking;and the strong men shall bow themselves; it is strange the Targum and Midrash should interpret this of the arms, designed in the former clause; Jarchi and Aben Ezra, more rightly, of the thighs; it takes in thighs, legs, and feet, which are the basis and support of the human body; and are strengthened for this purpose, having stronger muscles and tendons than any other parts of the body; but these, as old age comes on, are weakened and distorted, and bend under the weight of the body, not being able, without assistance, to sustain it;and the grinders cease because they are few; the Targum is,"the teeth of the mouth:''all agree the teeth are meant; only the Midrash takes in the stomach also, which, like a mill, grinds the food.