There is no real knowledge of Christ and His truth without purity of heart. The man who has no music in his soul can never be brought to understand the deep harmonies of the great masters and magicians of sound. The man who has no eye for beauty can never be brought to bow his spirit before some of those embodiments of loveliness and sublimity which the painter's brush has cast upon the canvas. And the man who has no longings after purity, nor has attained to any degree of moral conformity with the divine image, is not in possession of the sense which is needed in order that he should understand the 'deep things of God.'
The scholars in this school have to wash their hands before they go to school, and come there with clean hands and clean hearts. Foulness and the love of it are bars to all understanding of God's truth. And, on the other hand, the truest inducements, motives, and powers for purity are found in that great word which is all 'according to godliness,' and is meant much rather to make us good than to make us wise.
So, in this designation of the teaching Spirit as holy, there lie lessons for two classes of people. All fanatical professions of possessing divine illumination, which are not warranted and sealed by purity of life, are lies or self-delusion. And, on the other hand, coldblooded intellectualism will never force the locks of the palace of divine truth, but they that come there must have clean hands and a pure heart; and only those who have the love and the longing for goodness will be wise scholars in Christ's school. Your theology is nothing unless its distinct outcome is morality, and you must be prepared to accept the painful, the punitive, the purifying influences of that divine Spirit on your moral natures if you want to have His enlightening influences shining on the 'truth as it is in Jesus.' 'If any man wills to do His will, he,' and only he, 'shall know of the doctrine.' Knowledge and holiness are as inseparable in divine things as light and heat.
And still further note that this great Teacher is 'sent by God' in Christ's name. That pregnant phrase, 'In My name,' cannot be represented by any one form of expression into which we may translate it, but covers a larger space. God in Christ's name sends the Spirit. That is to say, in some deep sense God acts as Christ's representative; just as Christ comes in the Father's name and acts as His representative. And, again, God sends in Christ's name; that is, the historical manifestation of Christ is the basis on which the sending of the Spirit is possible and rests. The revelation had to be complete before He who came to unfold the meaning of the revelation had material to work upon. The Spirit, which is sent in Christ's name, has, for the basis of His mission, and the means by which He acts, the recorded facts of Christ's life and death, these and none other.
And then note finally about this matter, the strong and unmistakable declaration here, that that divine Spirit is a person: 'He shall teach you all things.' They tell us that the doctrine of the Trinity is not in the New Testament. The word is not, but the thing is. In this verse we have the Father, the Son, and the Spirit brought into such close and indissoluble union as is only vindicated from the charge of blasphemy by the belief in the divinity of each. Just as the Apostolic benediction, 'The grace of our Lord Jesus Christ, and the love of God the Father, and the communion of the Holy Spirit' necessarily involves the divinity of all who are thus invoked, so we stand here in the presence of a truth which pierces into the deeps of Deity. That divine Spirit is more than an influence. 'He shall teach,' and He can be grieved by evil and sin. I do not enlarge upon these thoughts. My purpose is mainly to bring them out clearly before you.