The New Testament considered by itself as a body of teaching is such an advance on all that preceded it as to be quite unique in the history of the world. The ideas conveyed in the Old Testament are absorbed, transformed, completed, so as to make them as a whole entirely new; and to these are added entirely new ideas sufficient by themselves to form a whole system of doctrine. And because of this it is difficult to speak of the new teaching as having grown out of the old.
But the Old Testament covers many centuries, and within its range we can trace a steady growth, and that growth always of the same character, and always pointing towards what the Gospel finally revealed. The strength of the moral sentiment in the earlier books is always assigned to the belief in, and reverence for, Almighty God. It is evidently held to be more important to believe in God and to fear Him than to see the perfection of His holiness. If we distinguish between Religion and Morality, Religion is made the more important of the two. It is more important to recognise that the holy God exists and reigns than to see clearly in what His holiness, and indeed all holiness, consists. The sentiment of reverence is more important than the perception of that universality which we now know to be the essential characteristic of the Moral Law. In analysing the origin and nature of Religion in the second of these Lectures, it was necessary to follow the order of thought, and beginning with Duty to end with God. But the order of fact is not the same. In actual fact man began with God and ends with a clearer perception of Duty. Hence in all the earlier stages the morality is imperfect. The profaneness of Esau is a serious offence. The ungenerous temper, the unfairness and duplicity of Jacob are light in comparison. Truth is not an essential. Blood-shedding and impurity when in horrible excess are treated as most grievous sins; but restrained within limits are easily condoned. Women are placed below their true and natural place; polygamy if not distinctly allowed is certainly condoned; divorce is permitted on one side, not on the other. Slavery is allowed though put under regulation. But the unity and spirituality of God are guarded with the strongest sanctions, and nothing could be said against idolatry and polytheism now, in sterner and clearer language than was used then. The reverence for God required then was as great as the reverence required now. But the conception of the holiness which is the main object of that reverence has changed; has in fact been purified and cleared. And the change is traceable in the Old Testament. The prophets teach a higher morality than is found in the earlier books. Cruelty is condemned as it had not been before. The heathen are not regarded as outside God's love, and the future embraces them in His mercy even if the present does not. Conscience begins to be recognised and appealed to. Idolatry is not merely forbidden, its folly is exposed; it is treated not only with condemnation, but with scorn. Individual responsibility is insisted on. Children are not held responsible for their fathers, though the inheritance of moral evil and of the consequences of moral evil is never denied. And even trust in God rises to a higher level in Habakkuk's declaration that that trust shall never be shaken by any calamity that may befall him, than in the earlier belief that calamities would never befall those who held fast that trust.
If we review this progress in moral teaching we recognise that it corresponds to the natural and for the most part unconscious working of that instinctive test which, as was pointed out before, we apply to all moral questions, the test of universality. The pivots of all the prophetical teaching are the incessant inculcation of justice and mercy; justice which requires us to recognise the rights of others side by side with our own; mercy which demands our sympathy with the feelings of other creatures that can feel.
We are bound to recognise the claims of others to equal treatment with ourselves, and any refusal or apparent refusal to do so must be justified by a universal rule applicable to all alike. The perpetual attempt to justify exceptions in this way is sure to end in diminishing the number of those exceptions. If we are compelled to think much of the position of woman in marriage, we are sure at last to come to Malachi's declaration that God hateth putting away. If we are compelled to think of the position of slaves, we cannot continue for ever to believe that there are some beings with consciences and free wills, who nevertheless, because of the accidents of their lives, have no rights at all; and we acknowledge the righteousness of Jeremiah's denunciation of the breach of covenant when the nobles of Judah re-enslaved those whom they had solemnly emancipated. If we think of the nature of responsibility and the justification of punishment, we find it impossible to believe that an innocent man shall be rightly punished for the wrong-doing of another, even if that other be his father or his mother; and we are convinced that Ezekiel is speaking God's words when he proclaims on God's behalf that 'the soul that sinneth it shall die; the son shall not bear the iniquity of the father, neither shall the father bear the iniquity of the son.' And once more, whatever divine purpose gave the chosen people a priority among all peoples in knowledge of divine will and possession of divine favour, it is impossible to find any rule by which this priority shall for ever exclude all other peoples from being within the range of God's manifested love; and conscience cannot but accept as a divine message that the Gentiles also shall come to the Heavenly 'Light, and their kings to the brightness of His rising.' So again, to turn from justice to mercy, we recognise that we are bound to spare pain to all creatures that can feel, and this duty can only be set aside by some higher duty which makes that pain the means to a higher moral end. And if we are set by our consciences to seek for some rule of universal application for this purpose, it becomes perpetually clearer that nothing can excuse cruel punishments inflicted on criminals or enemies, or hard-hearted indifference to the poor and the weak. Our own nature cries out for kindness in our pain, and that very cry from within compels our consciences to listen to the cry from without. And the denunciations of cruelty and oppression we recognise as we hear them to be the voice of God.
But however true it be that this progress corresponds exactly throughout with the necessary working of the great moral principles implanted in the spiritual faculty, it nevertheless remains true also that all this teaching in its successive stages is given by men who did not profess to be working out a philosophical system, but who claimed to bring a message from God, to speak by His authority, and in many cases to be trusted with special powers in proof of possessing that authority. Looking back over it afterwards we can see that the teaching in its successive stages was a development, but it always took the form of a revelation. And its life was due to that fact. As far as it is possible to judge, that union between Morality and Religion, between duty and faith, without which both religion and morality soon wither out of human consciences, can only be secured—has only been secured—by presenting spiritual truth in this form of a Revelation.
When we pass to the New Testament, all that has previously been taught in the Old, in so far as it is related to the new teaching at all, is related as the bud to the flower. The development, if it be indeed a development, is so great, so sudden, so strange, that it seems difficult to recognise that it is a development at all.
First, the morality is in form, if not in substance, absolutely new. The duty of justice and mercy is pushed at once to its extreme limits, even to the length of entire self-surrender. The disciple has his own rights no doubt, as every other man has his; but he is required to leave his rights in God's hands and to think of the rights of others only. The highest place is assigned to meekness in conduct and humility in spirit. The humility of the Sermon on the Mount may possibly by careful analysis be shown to be identical at bottom with the magnanimity of Aristotle's Ethics. But the presentation of the two is so utterly opposed that in the effect on life the identity is altogether lost. And as justice and mercy, so too self-discipline is pushed as far as it can go. Instead of the enjoyment of life being an integral part of the aim set before the will, hunger and thirst for righteousness, and penitence for failure in keeping to it, are to fill up the believer's hopes for himself. Of inward satisfaction and peace he is often assured; but these, and these only, are the means to that peace. The disciple's life is to consist in bearing the cross, and bearing it cheerfully; in returning good for evil, and love for indifference and even for hatred; in detaching his affections from all the pleasures to be obtained from external things; in fixing his trust and his love on his Eternal Father. Taken as a whole, this is quite unlike all moral teaching that preceded it, and there is no indication that any philosophy could ever have evolved it. It has fastened on the human conscience from the day that it was uttered; and whatever moral teaching since has not been inspired from this source has soon passed out of power and been forgotten. We find when we examine that it exactly agrees with the fundamental teaching of the spiritual faculty when that teaching is applied to such creatures as we are, and to such a God as the New Testament sets before us. But we find it impossible to assert that by any working of human thought this morality could have been obtained by the spiritual faculty unaided. On the contrary, it seems more near the truth to say that we could never have obtained so clear a conception of the great Moral Law, if the teaching of the New Testament had not enlightened and purified the spiritual faculty itself. And to this is to be added that the moral teaching of the New Testament recognises what we may now almost consider a proved necessity of our nature, or at least a sure characteristic of the government of the world, that perpetual progress without which nothing human seems to keep sweet and wholesome. Perfect as the New Testament morality is in spirit, it is nevertheless imperfect in actual precepts. It leaves questions to be solved some of which have not been solved yet. It left slavery untouched, though assuredly doomed. It said nothing of patriotism. It gave no clear command concerning the right use of wealth. It laid down no principles for the government of states, though such principles must have a moral basis. There has been a perpetual growth in the understanding and in the application of this perfect teaching, and there will yet be a growth. Of no philosophical system of morals is it possible to say the same.
But in the second place, the New Testament contains not only a new morality, it contains also a new account of human nature. The mystery of that discord which makes the noblest and best of human souls a scene of perpetual internal conflict is acknowledged and its counterpart in God's dealings with mankind is set forth. The struggle between the spiritual faculty asserting its due supremacy, and the lower passions and appetites, impulses and inclinations, is so described by Saint Paul that none have ever since questioned his description with any effect. And our Lord's teaching of our absolute dependence on God and helplessness without Him; and Saint John's teaching that the whole world, outside Christ, 'lieth in the wicked one,' lay down the same truth. And as the mystery of moral evil in mankind is thus set forth, so too the mystery of the remedy for that evil. In the love of God shown in the Cross of Christ, in our union with God through that same Death upon the Cross is the power which conquers evil in the soul and carries a man ever upward to spiritual heights. And as all profounder thinkers have confessed the truth of the account thus given of the internal contradiction of man's moral nature, so have all believers borne witness (and only they could bear witness) to the account thus given of the solution of that contradiction and the renovation of that nature. Millions have lived and died in the Christian faith since the teaching recorded in the New Testament was given, and among them have been the purest, the justest, the most self-sacrificing, the most heavenly-minded of mankind. And they all concur in saying that the one stay of all their spiritual lives has been communion with God through Christ.
Thirdly, the New Testament affirms with a clearness previously unknown the immortality of the soul and the future gift of that spiritual body which shall in some way spring from the natural body as the plant grows from the seed. There had grown up, no doubt quite naturally, anticipations of this doctrine and ever stronger and more deeply-rooted persuasion that it must be true. But it is revealed in the New Testament as it is taught nowhere else, and it is sealed by the Resurrection of our Lord, ever since then the historical centre of the Christian Faith. How exactly it harmonises with the teaching of the spiritual faculty I have pointed out before.
And, lastly, the New Testament not only tells us what never was told before of man's nature as a spiritual being and of his destiny hereafter; it tells also what was never told elsewhere of the nature of God and of the relations between Him and His creature man. The unity and spirituality of the Godhead so strenuously insisted on in the Old Testament, is no less insisted on in the New. But the mysterious complexity embraced within that unity, though darkly hinted at in the older teaching, is nowhere clearly set forth, but in the latter. We may find anticipations of the teaching of St. Paul and St. John, and of our Lord Himself as recorded by St. John, in the Book of Proverbs, in the Prophets, in the Rabbinical writers between the Prophets and the New Testament, and we can see in Philo to what this finally came unaided by Revelation. But the Christian teaching on our Lord's nature and on the Incarnation is distinct from all this. And it is in the Christian form, and only in that form, that the doctrine has satisfied the spiritual needs of the great mass of believers.