This passage is one of those in which the purity and holiness peculiar to the Gospel seem to be foretokened in the morality of the prophetic canon. Isaiah has been termed the Evangelical Prophet; and he is so, not more in the transcendent clearness of his predictions of evangelic facts, than in the corresponding brightness of his anticipations of evangelic holiness. As the inspired writers approached the great centre of purity, they became more and more deeply tinged with the glory they were approaching. The twilight clouds were red with the coming Sun.
I. Isaiah and his brother-prophets were holier and heavenlier and richer in the works of love upon an anticipated Christ than we are in a Christ already our crucified example. These men of God knew no divorce between belief and love, between living perpetually in the presence of a benevolent Lord and imitating His benevolence to their fellow-creatures. As it is the spirit of truth that has solemnised the union of the principle of faith with the works of charity, so it is, and in all ages has been, the master policy of the spirit of evil to effect their separation. This same purpose of separation which in darker ages the enemy of man sought to accomplish by making faith stand for a catalogue of superstitious observances similar to the fasts of which the prophet speaks in the text he now attempts to accomplish by exaggerating and perverting its more legitimate signification.
II. The whole religious providence of God towards man in every age has been a system operating by the combined influences of faith and love, both directed towards His own perfect essence. In our existing condition, what is faith but love relying on support? What is love but faith forgetting the support in the supporter? Every progressive step in attaining habits of compassion and kindness upon earth must necessarily be a step towards estimating and loving Him who is the essential Spirit of benevolence. The love of man is the type and shadow of the love of God the first step upon a pathway that conducts to paradise. The people of God are here engaged with the rudiments and images of those affections which are to be the duty and the happiness of their eternity.
W. Archer Butler, Sermons Doctrinal and Practical,2nd series, p. 148.
References: Isaiah 58:6; Isaiah 58:7. T. Dale, Penny Pulpit,No. 2977; W. M. Punshon, Sermons,2nd series, p. 317. Isaiah 58:6-8. S. Pearson, Christian World Pulpit,vol. xii., p. 225.