Then the kings countenance changed,.... Or, "his brightness" ; his ruddy countenance, his florid looks, his gay airs; all his jollity and mirth, that appeared in his face, were changed into paleness, sadness, and confusion:and his thoughts troubled him; what should be the meaning of this; perhaps he might immediately fear it presaged ruin and destruction to him; the sins of his former life might at once come into his thoughts, and those particularly he had now been guilty of; his luxury and intemperance, his idolatry and profanation of the vessels of the sanctuary, which his conscience might accuse him of, and give him great distress and trouble:so that the joints of his loins were loosed; or, "the girdles of his loins" ; which were loosed or broke, through the agitation he was in; or he was all over in a sweat, so that he was obliged to loose his girdle; or, as persons in great fear and consternation, he was seized with a pain in his back; it opened as it were; nor could he hold his urine; as Grotius and others; see Isa 45:1, where this seems to be prophesied of:and his knees smote one against another; as is the case of persons in a great tremor, or under a panic.
"Et subito genua intremuere timore".--Ovid. yhwyz "splendores ejus", Montanus, Vatablus, Michaelis.