And the Word became flesh and lived among us, and we have seen his glory, the glory as of a father’s only son, full of grace and truth.I am going to focus on the italicized phrase.
What is the relation between grace and truth? Do the two contradict one another, or are they rather complementary? If you are being gracious, must you set aside the truth, and likewise if you are being truthful, must you set aside grace? Or do the two belong together in some way?
John says that the Word took on human nature and lived among us. And while the impact left upon the apostles and disciples of Jesus was certainly manifold, he also takes the time to comment upon the lessons learned from the incarnate Word with regards to the relationship of grace and truth. Christ was full of both grace and truth, not only one or the other. The person of Christ himself shows us that grace and truth are compatible with one another, that they are capable of reconciliation, though things may seem otherwise to us at times.
Christ did not hold back from speaking the truth. Jesus tells Pilate: For this I was born, and for this I came into the world, to testify to the truth (18:37). And we read Christ regularly speaking in rather harsh terms towards those who did not believe in him, or whose faith was imperfect, telling them that their father was the Devil, that their hearts are murderous, that they did not believe in him because they did not know God, and so on. He famously tells the Pharisees, for example, that he is the good shepherd who lays down his life for the sheep, but they do not believe in him because they are not his sheep. Calvinists appeal to this passage (among others) to demonstrate their doctrine of limited or definite atonement.
But in interpreting these passages, we have to remember that Christ is full of both grace and truth. The truth is never separate from grace, and neither is grace ever separate from or apart from the truth. How can the harsh word of truth -- e.g., that a person's father is the devil -- be reconciled to grace? Very simply: if its purpose is not empty condemnation but rather salvation, repentance, restoration to God, liberation from sin and darkness. When the word of truth is uttered with the genuine intention of accomplishing salvation, then truth is grace, i.e. favor.
Take, then, as an example the following words of Christ: Whoever is from God hears the words of God. The reason you do not hear them is that you are not from God (John 8:47), If we were to interpret Christ in some predestinarian fashion as declaring his listeners to be reprobates, destined for destruction, this would be truth bereft of any grace whatsoever. There would be no favor accorded to his listeners through such an announcement, understood in such a system!
On the contrary, a reading which is simultaneously truthful as well as gracious understands Christ's words in the following way: he alerts them of their spiritual deception for the sake of provoking repentance and reconciliation to God. His harsh words reveal their dangerous state, not for the sake of bringing them to despair or hardening them even further (though, if they choose, this may be their response), but rather for the sake of inspiring them to search for the truth which they lack. In this way, he will be acting for their sake, in their favor, or in other words, out of grace.
Christ is full of grace and truth: I propose this as a general hermeneutical principle for interpreting all the words of Christ, however harsh and unforgiving and unyielding they may seem. His purpose is always salvific and salutary, even if in the obduracy of sinners his words are not received in this way. In this way I am following St. Isaac the Syrian, who wrote with such passion:
Among all His actions there is none which is not entirely a matter of mercy, love and compassion: this constitutes the beginning and the end of His dealings with us (Second Part 39, §22).