III. Again, the tone of St. Peter's sermon was remarkable because of its enlarged and enlightened spirituality. It proved the Spirit's power in illuminating the human consciousness. St. Peter was rapidly gaining a true conception of the nature of the kingdom of God. He enunciates that conception in this sermon. He proclaims Christianity, in its catholic and universal aspect, when he quotes the prophet Joel as predicting the time when the Lord would pour out His Spirit upon all flesh. St. Peter does not indeed seem to have realized all at once the full significance of his own teaching. He did not see that his words applied to the Gentiles equally with the Jews, sounding the death-knell of all national exclusiveness in religion. Had he seen the full meaning of his own words, he would not have hesitated so much about the baptism of Cornelius and the admission of the Gentiles. It has been found true, not only of St. Peter, but of teachers, reformers, politicians, statesmen, that they have not at once recognised all the vast issues and undeveloped principles which lay wrapped up in their original message. The stress and trial of life alone draw them out, at times compelling their authors to regret their earlier actions, at other times leading them to follow out with intensified vigour the principles and movements which they had themselves set in operation. Luther, when he protested against indulgences; Erasmus, when he ridiculed the ignorance of the monks and advocated the study of the Greek New Testament; John Hampden, when he refused to pay ship money; or Bishop Ken, when he declined obedience to the orders of King James II.;--none of them saw whereunto their principles would necessarily grow till time had thoroughly threshed their teaching and their actions, separating the husk of external circumstances, which are so variable, from the kernel of principle, which is eternally the same, stern, severe, inexorable, in its operations. So it was with St. Peter, and still earlier with the prophets. They sang of and preached a universal religion, as in this passage, but yet none of them realized the full scope and meaning of the words they had used, till a special revelation upon the housetop at Joppa compelled St. Peter to grasp and understand and apply the principles he had been already proclaiming.