This was a kind of service in which he was quite at home, and in his quiet northern home doubtless it kept him constantly employed. His English friends had not the leisure necessary to do the work in the thorough style in which he performed it. How diligently he laboured in this field, the facts already stated attest.
But the grandest fruit of his genius is undoubtedly his Apology. The address to the king is dated Nov. 25th, 1675; the Latin edition is dated Amsterdam, 1676. He was therefore only twenty-seven years of age when his masterpiece was completed; and as it was first published, so it stands to-day, unaltered. His genius matured early, though to the great perplexity of our human judgment, early maturity was followed by early death. For three or four years, his English brethren had been struggling with an unusually strong tide of misrepresentation and obloquy. He could not be a passive looker-on now that God had given him rest from persecution. He would endeavour to state the opinions of his brethren, and the rationale of them, with a fulness for which they had neither time nor opportunity. It was a brotherly and chivalrous feeling, and it had its own reward. The work was at once accepted as a standard exposition of Quakerism. It has been profusely eulogised by many who have not accepted the creed it defends. Even Voltaire has warmly praised its pure Latinity. He called it "the finest Church Latin that he knew." Sir James Mackintosh in his "Revolution in England," calls it "a masterpiece of ingenious reasoning, and a model of argumentative composition, which extorted praise from Bayle, one of the most acute and least fanatical of men." The writer in the "Theological Review," from whom we have already quoted, is enthusiastic in his admiration of it. After speaking of Rutherford's "Letters," and Scougal's "Life of God in the Soul of Man," he proceeds, "Greater, where they were greatest, than Rutherford or Scougal, was Robert Barclay; it is a country's loss that his splendid Apologia should be left in the hands of a sect. Here, indeed, is a genuine outcome of the inner depth of the nation's worship; something characteristic and her own; a gift to her religious life akin to her profoundest requirements; and if she did but know it, far worthier of the acceptance of her people than any religious aid which she has ever welcomed from the other side of the border; more satisfying to the intellect than the close scholastic conclusions of the English divines at Westminster; more full of melody to the soul than even the rude music of those ballad psalms which the Kirk had not been too proud to adapt from the version of the Cornish statesman. One great original theologian, and only one, has Scotland produced; he it is the history of whose life and mind we shall endeavour to approach in the present Article." Theol. Review, 1874, p. 528.
We must not leave the Apology without referring to its manly and honest preface. It has been praised as heartily as the book itself. In an age of fulsome flattery, it is unique in its appeal to the better nature of King Charles, whom the writer begs not to despise the singular mercies which God had shown him. On Barclay's return to London from Holland, he probably presented a copy to the king; and it is to the credit of that monarch that, far from taking offence at the plain speaking of his Quaker kinsman, we find him ever after showing him special favour. Penn and Barclay seem alike to have possessed the power of drawing out the best side of the characters of Charles II. and his brother James II. This fact must be borne in mind in considering the charges laid against the former because of intimate relations with the Court.
From the Continent, Barclay returned to London, where he heard that his father and other of his Aberdeen friends had been thrown into prison for "holding conventicles." He immediately began to devise measures for their release. He had a letter from the Princess Elizabeth to her brother Prince Rupert. He presented this, met of course with a civil reception, and took the opportunity to obtain the Prince's concurrence with a petition which he was presenting to the king. He also wrote to the Princess to support his application, and then presented his petition. His plea is that a difference should be made between the peaceable and loyal Quakers, and those against whom the laws were directed. Unfortunately Prince Rupert was indisposed, and unable to keep his promise. So as the petition was vigorously opposed, his memorial was passed on to the Scotch Privy Council, with such a cool endorsement that it took no effect.
It was on this errand that he first sought the Duke of York, afterwards James II. He himself has told the story in his "Vindication." "Being at London and employed by my friends to obtain a liberty for them out of their imprisonment at Aberdeen for the single exercise of their conscience, and not being able to gain any ground upon the Duke of Lauderdale, in whose hands was the sole management of Scots affairs at that time, I was advised by a Friend to try the Duke of York, who was said to be the only man whom Lauderdale would bear to meddle in his province, or who was like to do it with success. And having found means of access to him, I found him inclined to interpose in it, he having then and always since to me professed himself to be for liberty of conscience. And though not for several years, yet at last his interposing proved very helpful in that matter."
The reply of the Princess Palatine to Robert Barclay's request, is interesting as a specimen of the religious correspondence of these illustrious friends. She says, "Your memory is dear to me, so are your lines and exhortations very necessary. I confess also myself spiritually very poor and naked; all my happiness is, I do know I am so, and whatever I have studied or learnt heretofore is but dirt in comparison with the true knowledge of Christ. I confess my infidelity to this Life heretofore, by suffering myself to be conducted by false, politic lights. Now that I have sometimes a small glimpse of the true Light, I do not attend it as I should, being drawn away by the works of my calling, which must be done; and as your swift English hounds I often overrun my scent, being called back when it is too late."
In his reply, Barclay tells of the non-success of his efforts to obtain the release of his friends, and yet adds with calm heroism, "I this day take my journey towards them, not doubting but I shall also share their joys." Nor was he mistaken. Soon after reaching Aberdeen, he was arrested and placed in the Tolbooth. This gaol was divided into two parts, the lower, which was vile, the upper, which was worse. Robert Barclay was allowed a place in the lower prison, but those who were arrested with him were thrust into the upper prison. Here shortly afterwards they were joined by David Barclay, who had been released only to fall again into the clutches of the enemy.
The news of Robert Barclay's commitment to prison reached his royal friend Elizabeth the next month (Dec. 1676). She at once wrote to console him. "I am sure that the captivers are more captive than you are, being in the company of him that admits no bonds, and is able to break all bonds." She also wrote at once to her brother Prince Rupert to use his influence with the king on his behalf.
Her letter put the case plainly and well. "I wrote you some months ago by Robert Barclay who passed this way, and hearing I was your sister, desired to speak with me. I knew him to be a Quaker by his hat, and took occasion to inform myself of all their opinions; and finding they were accustomed to submit to magistrates in real things, omitting the ceremonial, I wished in my heart the King might have many such subjects. And since I have heard that notwithstanding his Majesty's most gracious letters in his behalf to the Council of Scotland, he has been clapped up in prison with the rest of his friends, and they threaten to hang them, at least those they call preachers among them, unless they subscribe their own banishment; and this upon a law made against other sects that appeared armed for the maintenance of their heresy; which goes directly against the principles of those which are ready to suffer all that can be inflicted, and still love and pray for their enemies. Therefore, dear brother, if you can do anything to prevent their destruction, I doubt not but you will do an action acceptable to God Almighty, and conducive to the service of your royal master. For the Presbyterians are their violent enemies, to whom they are an eyesore, as being witnesses against all their violent ways. I care not though his Majesty see my letter. It is written out of no less an humble affection for him, than most sensible compassion for the innocent sufferers."