The theological ideas of the prophecy are different from those of Isaiah. Unique emphasis is laid on the creative power of Jehovah, and this thought is applied to the case of forlorn Israel with overwhelming effect; for it is none other than the eternal and omnipotent God that is about to reveal Himself as Israel's redeemer, in fulfilment of ancient words of prophecy, xliv. 7, 8. This very attitude to prophecy marks the book as late; it would not be possible in a pre-exilic prophet. But the most original conception of the book is one which finds no parallel whatever in Isaiah, viz. the suffering servant of Jehovah. This servant is the exclusive theme of the four songs, xlii. 1-4, xlix. 1-6, l. 4-9, lii. l3-liii. 12; but more or less he is involved in the whole prophecy. The function of the servant is to give light to the Gentiles--in other words, to bring the world to a knowledge of Jehovah (cf. xlii. 1, xlv. 14). Who is the servant? The difficulty in answering this question is twofold: (i.) while the servant is often undoubtedly a collective term for the people of Israel, xli. 8, xliv. 1, 2, the descriptions of him, especially in the songs alluded to, are occasionally so intimately personal as to seem to compel an individual interpretation (cf. liii.). But in this connection we have to remember the ease with which the Oriental could personify, and apply even the most personal detail to a collective body. "Grey hairs are upon him," says Hosea, vii. 9, not of a man but of the nation; and Isaiah himself, i. 6, described the body politic as sick from the crown of the head to the sole of the foot (cf. Ezek. xvi., xxiii). Clearly, therefore, individual allusions do not necessarily compel an individual interpretation; and there is no reason in the nature of the case, and still less in the context, to assume a reference to any specific individual. The songs are an integral part of the prophecy: the function of the servant is the same, and the servant must also be the same in both. Indeed one passage in the second song, xlix. 3, expressly identifies the servant with Israel; and in liii., an intensely personal chapter, where the servant, after death, is to rise again and take his place victoriously in the world, the collective interpretation of the servant as Israel, emerging triumphantly from the doom of exile, is natural, if not necessary.