I. Luke sharply parts off the Baptist's work as a preacher of repentance and plain morality from his work as the herald who preceded the king. The former is delineated in verses 7-14, and its effect was to set light to the always smouldering expectation of the Messiah. The people were ready to rally round him if he would say that he was the coming deliverer. It was a real temptation, but his unmoved humility, which lay side by side with his boldness, brushed it aside, and poured an effectual stream of cold water on the excitement. 'John answered' the popular questionings, of which he was fully aware, and his answer crushed them. In less acute fashion, the same temptation comes to all who move the general conscience. Disciples always seek to hoist their teacher higher than is fitting. Adherence to him takes the place of obedience to his message, and, if he is a true man, he has to damp down misdirected enthusiasm. Mark John's clear apprehension of the limitations of his work. He baptized with water, the symbol and means of outward cleansing. He does not depreciate his position or the importance of his baptism, but his whole soul bows in reverence before the coming Messiah, whose great office was to transcend his, as the wide Mediterranean surpassed the little lake of Galilee. His outline of that work is grand, though incomplete. It is largely based upon Malachi's closing prophecy, and the connection witnesses to John's consciousness that he was the Elijah foretold there. He saw that the Messiah would surpass him in his special endowment. Strong as he was, that other was to be stronger. Probably he did not dream that that other was to wield the divine might, nor that His perfect strength was to be manifested in weakness, and to work its wonders by the might of gentle, self-sacrificing love. But, though he dimly saw, he perfectly adored. He felt himself unworthy (literally, insufficient) to be the slave who untied (or, according to Matthew, 'bore') his lord's sandals. How beautiful is the lowliness of that strong nature! He stood erect in the face of priests and tetrarchs, and furious women, and the headsman with his sword, but he lay prostrate before his King. Strength and royal authority were not all that he had to proclaim of Messiah. 'He shall baptize you in the Holy Ghost and fire.' We observe that the construction here is different from that in verse 16 ('with water'), inasmuch as the preposition 'in' is inserted, which, though it is often used 'instrumentaly,' is here, therefore, more probably to be taken as meaning simply 'in.' The two nouns are coupled under one preposition, which suggests that they are fused together in the speaker's mind as reality and symbol.