Many stories were told in Scotland of the debating powers of young Gillespie as seen on the floor of the Westminster Assembly.  Selden was one of the greatest lawyers in England, and he had made a speech one day that both friend and foe felt was unanswerable.  One after another of the Constitutional and Evangelical party tried to reply to Selden’s speech, but failed.  ‘Rise, George, man,’ said Rutherford to Gillespie, who was sitting with his pencil and note-book beside him.  ’Rise, George, man, and defend the Church which Christ hath purchased with His own blood.’  George rose, and when he had sat down, Selden is reported to have said to some one who was sitting beside him, ’That young man has swept away the learning and labour of ten years of my life.’  Gillespie’s Scottish brethren seized upon his note-book to preserve and send home at least the heads of his magnificent speech, but all they found in his little book were these three words:  Da lucem, Domine; Give light, O Lord.  Rutherford had foreseen all this from the days when Gillespie and he talked over Aquinas and Calvin and Hooker and Amesius and Zanchius as they took their evening walks together on the sands of the Solway Firth.  It is told also that when the Committee of Assembly was engaged on the composition of the Shorter Catechism, and had come to the question, What is God? like the able men they were, they all shrank from attempting an answer to such an unfathomable question.  In their perplexity they asked Gillespie to offer prayer for help, when he began his prayer with these words:  ’O God, Thou art a Spirit, infinite, eternal, and unchangeable in Thy being, wisdom, power, holiness, justice, goodness, and truth.’  As soon as he said Amen, his opening sentences were remembered, and taken down, and they stand to this day the most scriptural and the most complete answer to that unanswerable question that we have in any creed or catechism of the Christian Church.

As her best tribute to the talents and services of her youngest Commissioner, the Edinburgh Assembly of 1648 appointed Gillespie her Moderator; but his health was fast failing, and he died in the December of that year, in the thirty-sixth year of his age.  The inscription on his tombstone at Kirkcaldy ends with these sober and true words:  ’A man profound in genius, mild in disposition, acute in argument, flowing in eloquence, unconquered in mind.  He drew to himself the love of the good, the envy of the bad, and the admiration of all.’  Such was the life and work of George Gillespie, one of the most intimate and confidential correspondents of Samuel Rutherford;—­for it was to him that Rutherford wrote the words now before us, ‘Our apprehensions are not canonical.’