When the Spirit of Truth comes, he will lead you to the complete truth (Jn 16:13).
Four times in his final discourse at the Last Supper, according to St. John, Jesus speaks of the Holy Spirit, the Paraclete. He will be with us forever. He will teach us everything. He will bear witness to Jesus. He will convict the world of sin (14:16, 14:26, 15:26, 16:7-15). Now in Chapter 16 the discourse of Jesus circles back one last time to the Holy Spirit, giving him the title “Spirit of Truth”.
The Holy Spirit leads us to the complete Truth; that is, he leads us to God. The Spirit illuminates the mystery of Christ, who is the eternal Son of the Father. Speaking of his relationship with God the Father in today’s Gospel, Jesus says: All that the Father has is mine. That is: I share everything that the Father has, everything that he is, apart from this: that he is the Father and I am the Son. He is the origin; I am from him. As for the Holy Spirit, he too shares the divine nature. He too is God: perfectly one with, perfectly equal to the Father and the Son; yet also infinitely distinguished from each of them by the relationship of Person. Of him Jesus says in today’s Gospel: All he tells you will be taken from what is mine. We in the Latin Church read these words as pointing to the eternal procession of the Holy Spirit from both the Father and the Son: “qui ex Patre Filioque procedit”. Our Eastern Orthodox brethren, one with us in every other aspect of trinitarian doctrine, hold a different opinion on this particular point.
Of course the mystery of the Holy Trinity is beyond our understanding. We approach God with our shoes off, in profound humility; trembling, with the Angels, in both love and awe. Yet God who is infinitely “other” has chosen to reveal himself to us. He communicates with us; he gives himself to us; he invites us to share his own life. Specifically, he gives us the Spirit of Sonship, so that by the Holy Spirit we can boldly relate to God our Father with the very intimacy and joy of Christ (cf. Gal 4:6, Rm 8:15).
The Spirit of Truth will lead you to the complete truth. Because of divine Revelation, we cannot regard God as an unknown “X”. If the mystery of the Holy Trinity is too great for our comprehension, it’s not incoherent, and not contrary to reason. We can and must use very precise language about it. This language has been worked out through the life of the Church, especially in response to heresies. We believe that it conveys the truth, so that deliberately to contradict what it says is to speak what is false. Of course the Church has never claimed the authority to invent new doctrines. Great dogmatic theologians like St. Athanasius or St. Augustine did not know more about the Trinity than the Apostles did. Their whole effort was precisely to preserve intact the authentic Apostolic doctrine, to unfold what is already contained fully in Holy Scripture. They did this by exposing the errors of heretics, and also by exploring in new ways some of the implications of what has been revealed. By the light of the Holy Spirit the Catholic Church has recognised her own doctrine in the writings of these masters. We say that through them and through many others, until the end of time, her doctrine develops, or makes progress, towards an ever deeper, fuller understanding.
In principle the Spirit of Truth leads not just the whole Church, but also each individual member of the Church towards the complete truth. He illuminates the minds and hearts of each one of us, so that we understand in an ever new way God’s greatness, his goodness, his presence, his love. The Spirit leads us to apprehend more deeply not only how God is Three in One, but also how each of the divine Persons directly relates to us, loves us, draws us, indwells us. The Spirit can give these insights in any way or at any time, though usually they will come from prayer and meditation on Holy Scripture. Such insights, or moments of grace, will always be for us a cause of joy, and new life, and new wonder, and new fidelity, and new holiness.
Nowadays in our contemporary culture any absolute truth claim is regarded with suspicion, and considered politically incorrect. The prevailing secularism would permit us perhaps to hold something as true “for us”, but would expect us to concede the equal validity of any opposing truth claims. For her own part, the Catholic Church is committed to respectful and non-aggressive dialogue with people of other religions, or of no religion. Christians earnestly desire to live in peace and harmony with them, cooperating as far as possible in all matters of common concern. With the early Fathers of the Church, we rejoice to see “elements of truth and goodness” in non-Christian religions and philosophies. But our holy faith entirely excludes doctrinal relativism. We believe that the truth we hold is from God. It leads us to life and salvation. Not to know this truth is to walk in the darkness of ignorance or error, from which it is good for people to be delivered.
When false ideologies arise, they usually seek to impose themselves by force and fear. It is typical of their adherents to claim the moral high ground; to be earnest and sincere; and to demand universal and unconditional surrender. Christians have often suffered under them, even been crushed by them, but also many times have arisen to fight them, for the benefit of all. Of himself, the Holy Spirit draws us towards unity and peace. But where truth is denied, because he is the Spirit of Truth, the Holy Spirit’s gift may be to strengthen us for conflict, even for combat. One example of intolerant and aggressive un-truth in our own day is gender ideology. Orthodox Christianity cannot possibly accept it, for not only is it manifest nonsense, but it directly opposes our faith. Already those who have resisted its advance have found themselves intimidated, vilified, excluded, prosecuted, dismissed from their employment. Perhaps real martyrdom of blood will follow? Whatever the future brings, we will not capitulate to it.
The Holy Spirit will tell you of things to come says Jesus. He will tell the meaning of my coming death and resurrection and ascension and glorification. He will tell of the age of the Church. And he will point towards the completion of all things in eternal life. For there, says St. Paul, we shall know, even as we are known (cf. 1 Cor 13:12). There, according to St. John, we shall be like him, for we shall see him as he really is (1 Jn 3:2).