He shall drink of the brook in the way: this may be understood either,
1. Properly, to express the fervency and diligence of the Messias in the prosecution of his business; who having routed and destroyed the main body of his enemies forces, pursues those that fled with such eagerness, that he will not lose any time in refreshing himself, as might seem necessary after such hot and hard service, but will content himself with drinking a little water out of the brook which he finds in his way, that being a little refreshed therewith he may proceed with more rigour and efficacy in his work. And so this place alludes to the history of Gideon's three hundred men, who only lapped a little of the water; of whom see Jud 7. Or,
2. Metaphorically, to express the humiliation and passion of the Messias, and thereby to prevent a great mistake which might arise in men's minds concerning him, from the great successes and victories here ascribed to him, which might induce them to think that the Messias should be exempted from all sufferings, and be crowned with constant and perpetual triumphs. To confute this conceit, he intimates here that the Messias, before he should obtain that power and glory mentioned in the foregoing verses, should have a large portion of afflictions in the way to it, or whilst he was in the way or course of his life, before he came to his end or rest, and to that honour of sitting at his Father's right hand. Waters in Scripture do very frequently signify afflictions or sufferings, as Psalms 42:7, &c. To drink of them, signifies to feel or bear them, as Isaiah 51:17 Jeremiah 25:15, Jeremiah 49:12 Matthew 20:22; and in this case it may note Christ's willing submission to them. A brook or river of water is oft used in Scripture to express a great abundance, either of comforts, as Psalms 36:8, or of tribulations, Psalms 18:4, Psalms 124:4; and therefore may be more fitly used in this place than a cup, by which the afflictions of other men are commonly expressed, to intimate that the sufferings of the Messiah were unspeakably more and heavier than the sufferings of other men, and that he should drink up not a small cup, but the whole river or sea of his Father's wrath due to our sins. Therefore, which word may note either the effect or the consequent of his sufferings, shall he lift up the head, i.e. shall be delivered from all his sorrows and sufferings, and exalted to great glory, and joy, and felicity, as this phrase usually signifies, as Psalms 3:3, Psalms 27:6 Jeremiah 52:31, and oft elsewhere; as, on the contrary, to hang down the head, is a signification of great grief and shame, as Lamentations 2:10.