The thought of the unity of the Church is much in the Apostle's mind in this epistle. It is set forth in many places by his two favourite metaphors of the body and the temple, by the relation of husband and wife and by the family. It is contemplated in its great historical realisation by the union of Jew and Gentile in one whole. In the preceding context it is set forth as already existing, but also as lying far-off in the future. The chapter begins with an earnest exhortation to preserve this unity and with an exhibition of the oneness which does really exist in body, spirit, hope, lord, faith, baptism. But the Apostle swiftly passes to the corresponding thought of diversity. There are varieties in the gifts of the one Spirit; whilst each individual in the one whole receives his due portion, there are broad differences in spiritual gifts. These differences do not break the oneness, but they may tend to do so; they are not causes of separation and do not necessarily interfere with unity, but they may be made so. Their existence leaves room for brotherly helpfulness, and creates a necessity for it. The wiser are to teach; the more advanced are to lead; the more largely gifted are to encourage and stimulate the less richly endowed. Such outward helps and brotherly impartations of gifts is, on the one hand, a result of the one gift to the whole body, and is on the other a sign of, because a necessity arising from, the imperfect degree in which each individual has received of Christ's fulness; and these helps of teaching and guidance have for their sole object to make Christian men able to do without them, and are, as the text tells us, to cease when, and to last till, we all attain to the fulness of Christ. To Paul, then, the manifest unity of the Church was to be the end of its earthly course, but it also was real, though incomplete, in the present, and the emphasis of our text is not so much laid on telling us when this oneness was to be manifested as in showing us in what it consists. We have here a threefold expression of the true unity, as consisting in a oneness of relation to Christ, a consequent maturity of manhood and a perfect possession of all which is in Christ.

I. The true unity is oneness of relation to Christ.

The Revised Version is here to be preferred, and its 'attain unto' brings out the idea which the Authorised Version fails to express, that the text is intended to point to the period at which Christ's provision of helpful gifts to the growing Church is to cease, when the individuals composing it have come to their destined unity and maturity in Him. The three clauses of our text are each introduced by the same preposition, and there is no reason why in the second and third it should be rendered 'unto' and in the first should be watered down to 'in.'

There are then two regions in which this unity is to be realised. These are expressed by the great words, 'the unity of the faith and knowledge of the Son of God.' These words are open to a misunderstanding, as if they referred to a unity as between faith and knowledge; but it is obvious to the slightest reflection that what is meant is the unity of all believers in regard to their faith, and in regard to their knowledge. It is to be noted that the Apostle has just said that there is one faith, now he points to the realisation of that oneness as the very end and goal of all discipline and growth. I suppose that we have to think here of the manifold and sad differences existing in Christian men, in regard to the depth and constancy and formative power of their faith. There are some who have it so strong and vigorous that it is a vision rather than a faith, a trust, deep and firm and settled, to which the present is but the fleeting shadow, and the unseen the eternal and only reality; but, alas! there are others in whom the light of faith burns feebly and flickers. Nor are these differences the attributes of different men, but the same man varies in the power of his faith, and we all of us know what it is to have it sometimes dominant over our whole selves, and sometimes weak and crushed under the weight of earthly passions. To-day we may be all flame, to-morrow all ice. Our faith may seem to us to be strong enough to move mountains, and before an hour is past we may find it, by experience, to be less than a grain of mustard seed. 'Action and reaction are always equal and contrary,' and that law is as true in reference to our present spiritual life as it is true in regard to physical objects. We have, then, the encouragement of such a word as that of our text for looking forward to and straining towards the reversal of these sad alterations in a fixed and continuous faith which should grasp the whole Christ and should always hold Him. There may still be diversities and degrees, but each should have his measure always full. 'Thy Sun shall no more go down'; there will no longer be the contrast between the flashing waters of a flood-tide and the dreary mud-banks disclosed at low water. We shall stand at different points, but the faces of all will be turned to Him who is the Light of all, and every face will shine with the likeness of His, when we see Him as He is.

But our text points us to another form of unity—the oneness of the knowledge of the Son of God.

The Apostle uses an emphatic term which is very familiar on his lips to designate this knowledge. It means not a mere intellectual apprehension, but a profound and vital acquaintance, dependent indeed upon faith, and realised in experience. It is the knowledge for which Paul was ready to 'count all things but loss' that he might know Jesus, and winning which he would count himself to 'have apprehended.' The unity in this deep and blessed knowledge has nothing to do with identity of opinion on the points which have separated Christians. It is not to be sought by outward unanimity, nor by aggregation in external communities. The Apostle's great thought is made small and the truth of it is falsified when it is over-hastily embodied in institutions. It has been sought in a uniformity which resembles unity as much as a bundle of faggots, all cut to the same length, and tied together with a rope, resemble the tree from which they were chopped, waving in the wind and living one life to the tips of its furthest branches. Men have made out of the Apostle's divine vision of a unity in the faith and knowledge of the Son of God 'a staunch and solid piece of framework as any January could freeze together,' and few things have stood more in the way of the realisation of his glowing anticipations than the formation of the great Corporation, imposing from its bulk and antiquity, to part from which was branded as breaking the unity of the spirit.

Paul gives no clear definition here of the time when the one body of Christian believers should have attained to the unity of the faith and knowledge of the Son of God, and the question may not have presented itself to him. It may appear that in view of the immediate context he regards the goal as one to be reached in our present life, or it may be that he is thinking rather of the Future, when the Master 'should bring together every joint and member and mould them into an immortal feature of loveliness and perfection.' But the time at which this great ideal should be attained is altogether apart from the obligation pressing upon us all, at all times, to work towards it. Whensoever it is reached it will only be by our drawing 'nearer, day by day, each to his brethren, all to God,' or rather, each to God and so all to his brethren. Take twenty points in a great circle and let each be advanced by one half of its distance to the centre, how much nearer will each be to each? Christ is our unity, not dogmas, not polities, not rituals: our oneness is a oneness of life. We need for our centre no tower with a top reaching to heaven, we have a living Lord who is with us, and in Him, we being many, are one.

II. Oneness in faith and knowledge knits all into a 'perfect man.'

'Perfect,' the Apostle here uses in opposition to the immediately following expression in the next verse, of 'children.' It therefore means not so much moral perfection as maturity or fulness of growth. So long as we fall short of the state of unity we are in the stage of immaturity. When we come to be one in faith and knowledge we have reached full-grown manhood. The existence of differences belongs to the infancy and boyhood of the Church, and as we grow one we are putting away childish things. What a contrast there is between Paul's vision here and the tendency which has been too common among Christians to magnify their differences, and to regard their obstinate adherence to these as being 'steadfastness in the faith'! How different would be the relations between the various communities into which the one body has been severed, if they all fully believed that their respective shibboleths were signs that they had not yet attained, neither were already perfect! When we began to be ashamed of these instead of glorying in them we should be beginning to grow into the maturity of our Christian life.

But the Apostle speaks of 'a perfect man' in the singular and not of 'men' in the plural, as he has already described the result of the union of Jew and Gentile as being the making 'of twain one new man.' This remarkable expression sets forth, in the strongest terms, the vital unity which connects all members of the one body so closely that there is but one life in them all. There are many members, but one body. Their functions differ, but the life in them all is identical. The eye cannot say to the hand, 'I have no need of thee,' nor again the head to the feet, 'I have no need of you.' Each is necessary to the completeness of the whole, and all are necessary to make up the one body of Christ. It is His life which manifests itself in every member and which gives clearness of vision to the eye, strength and deftness to the hand. He needs us all for His work on the world and for His revelation to the world of the fulness of His life. In some parts of England there are bell-ringers who stand at a table on which are set bells, each tuned to one note, and they can perform most elaborate pieces of music by swiftly catching up and sounding each of these in the right place. All Christian souls are needed for the Master's hand to bring out the note of each in its place. In the lowest forms of life all vital functions are performed by one simple sac, and the higher the creature is in the scale the more are its organs differentiated. In the highest form of all, 'as the body is one, and hath many members, and all the members of the body, being many, are one body, so also is Christ.'

III. This perfect manhood is the possession of all who are in Christ.

The fulness of Christ is the fulness which belongs to Him, or that of which He is full. All which He is and has is to be poured into His servants, and when all this is communicated to them the goal will be reached. We shall be full-grown men, and more wonderful still, we all shall make one perfect man, and individual completenesses will blend into that which is more complete than any of these, the one body, which corresponds to the measure of the stature of the fulness of Christ.

This is the goal of humanity in which, and in which alone, the dreams of thinkers about perfectibility will become facts, and the longings that are deeply rooted in every soul will find their fulfilment. By our personal union with Jesus Christ through faith, our individual perfection, both in the sense of maturity and in that of the realisation of ideal manhood, is assured, and in Him the race, as well as the individual, is redeemed, and will one day be glorified. The Utopias of many thinkers are but partial and distorted copies of the kingdom of Christ. The reality which He brings and imparts is greater than all these, and when the New Jerusalem comes down out of heaven, and is planted on the common earth, it will outvie in lustre and outlast in permanence all forms of human association. The city of wisdom which was Athens, the city of power which was Rome, the city of commerce which is London, the city of pleasure which is Paris, 'pale their ineffectual fires' before the city in the light whereof the nations should walk.

The beginning of the process, of which the end is this inconceivable participation in the glory of Jesus, is simple trust in Him. 'He that is joined to the Lord is one spirit,' and he who trusts in Him, loves Him, and obeys Him, is joined to Him, and thereby is started on a course which never halts nor stays so long as the faith which started him abides, till he 'grows up into Him in all things which is the head, even Christ.' The experience of the Christian life as God means it to be, and by the communication of His grace makes it possible for it to become, is like that of men embarked on some sun-lit ocean, sailing past shining headlands, and ever onwards, over the boundless blue, beneath a calm sky and happy stars. The blissful voyagers are in full possession at every moment of all which they need and of all of His fulness which they can contain, but the full possession at every moment increases as they, by it, become capable of fuller possession. Increasing capacity brings with it increasing participation in the boundless fulness of Him who filleth all in all.