It is difficult to form a just or at least a full estimate of Leighton’s character. He stands almost alone in his age. In some respects he was immeasurably superior both in intellect and in piety to most of the Scottish ecclesiastics of his time; and yet he seems to have had almost no influence in moulding the characters or conduct of his contemporaries. One is half inclined to think that he would have shown himself a greater or at least a more complete man if a few natural weaknesses and imperfections had intermingled with his nobler qualities. So intense was his absorption in the love of God that little room seems to have been left in his heart for human sympathy or affection. Can it be that there was after all something to repel in his outward manner? Burnet tells us that he had never seen him to laugh, and very seldom even to smile. One can hardly forgive him for regarding Episcopacy so purely under the dry light of human reason after the horrible treatment which his excellent father had suffered from it. In other respects, too, he gives the impression of standing aloof from human interests and ties. It may go for little that he never married, but it was surely a curious idiosyncrasy in the man that he habitually cherished the wish (which was granted him) that he might die in an inn, where there could be no loving hand to support, no loving heart to cheer him. In fact, holy meditation seems to have been the one absorbing interest of his life. At Dunblane tradition still preserves the memory of “the good bishop,” silent and companionless, pacing up and down the sloping walk by the river's bank under the beautiful west window of his cathedral. And from a letter of the earl of Lothian to his countess it appears that, whatever other reasons Leighton might have had for resigning his charge at Newbattle, the main object which he had in view was to be left to his own thoughts. It is therefore on the whole not very wonderful that he was completely misjudged and even disliked both by the Presbyterian and the Episcopal party. Some of the bitter expressions of hatred towards him, however, on the part of the former, sound very strange to us who now know how holy, humble, and blameless the man really was. Thus in Naphtali it is said, “Mr Leighton, prelate of Dumblain, under a Jesuitical-like vizard of pretended holiness, humility, and crucifixion to the world, hath studied to seem to creep upon the ground, but always up the hill, toward promotion and places of more ease and honour, and as there is none of them all hath with a kiss so betrayed the cause and smitten religion under the fifth rib, and hath been such an offence to the godly, so there is none who by his way, practice, and expressions giveth greater suspicion of a popish affection, inclination, and design.” So also in the continuation of Robert Blair’s life by his son-in-law, William Ross, the most innocent of Leighton’s acts have a malicious interpretation put upon them. When he resigned Newbattle, he “pretended insufficiency for the ministry”; when he returned to Edinburgh as bishop and expressed an opinion in favour of the English liturgy and ceremonies, “it was suspected that he was popish and Jesuited”; when he refused the title of lord, and in other respects carried himself modestly and humbly, he was simply “a pawky prelate.” When he spoke in parliament in favour of the outed ministers, and thought that they ought to be “cherished and embraced” instead of persecuted, offending all the other prelates by the course he took, “it was difficult what to judge of his actings or sayings, he carried so smoothly among the ministers of his diocese.” Some, indeed, we are told, thought well of him, but others thought “that he spoke from a popish principle.” When he behaved sweetly and gently to the clergy of his diocese, telling them to hold their presbyteries and sessions as before, and suggesting without commanding any thing, it was “thought that he was but straking cream in their mouths at first.” When disgusted with the proceedings of the other bishops in “outing so many honest ministers and filling their places with insufficient and for the most part scandalous men,” and intimating his wish to demit his office in consequence, he was only “pretending to be displeased.” When the king wrote to the council that some of the most peaceable and moderate outed ministers might have liberty to preach, and Leighton pleaded that all might have the like liberty, it was “thought that he did this of purpose to oppose and crush it.”" Nothing that the good man could say or do brought upon him anything but suspicion and calumny. Even Wodrow, who generally gets credit for fairness and candour, tells us that “he was judged void of any doctrinal principles,” and that he was regarded “as very much indifferent to all professions which bore the name of Christian.”
It is worth while to set over against these uncharitable and malignant insinuations the estimate which his intimate friend Bishop Burnet formed of him. At the conclusion of his Pastoral Care, he says, “I have now laid together with great simplicity what has been the chief subject of my thoughts for above thirty years. I was formed to them by a bishop that had the greatest elevation of soul, the largest compass of knowledge, the most mortified and heavenly disposition, that I ever yet saw in mortal; that had the greatest parts as well as virtue, with the perfectest humility that I ever saw in man, and had a sublime strain in preaching, with so grave a gesture, and such a majesty of thought, of language, and of pronunciation, that I never once saw a wandering eye where he preached, and have seen whole assemblies often melt in tears before him; and of whom I can say with great truth that, in a free and frequent conversation with him for above two and twenty years, I never knew him say an idle word, or one that had not a direct tendency to edification; and I never once saw him in any other temper but that which I wished to be in, in the last minutes of my life.”