And praised be Jesus and Mary, now and forever. 
In the Gospel of St. John today, we are at the Last Supper with our Lord. He's just told them that he has to leave them and that they will be persecuted and put to death for bearing witness to the world. We heard him say a minute ago, "Behold, because I told you this, grief has filled your hearts," John 16:6. And so, he verbalizes and sympathizes with their interior turmoil and he offers a word of encouragement. As St. Augustine noted, commenting on this passage, he said, "Not having yet the inward consolation that the Holy Spirit was to impart, the disciples were afraid to lose the outward presence of Christ," which is completely understandable.
Our Lord reassures the disciples by saying, "I tell you the truth, it is better, it is to your advantage that I go, for if I do not go, the advocate or the counselor will not come to you, but if I go, I will send him to you," John 16:7. One thing we want to acknowledge or highlight here is the fact that everything that our Lord says and does, everything is to our advantage. Whatever he does or wants us to do, it's always for our good.
Next, we need to understand that in God's plan, the visible guide, meaning Jesus, he had to go away so that the invisible guide, the Holy Spirit, could arrive. That's how God intended it to be, at least after the fall. In today's gospel passage and in other places in St. John's gospel, our Lord calls the Holy Spirit the advocate or the counselor, or the helper, depending on the translation. The Greek word is parakletos. It was a legal term for an attorney or a spokesperson who defended the cause of the accused person in a courtroom.
The Catechism at number 692 says the Holy Spirit's name, the paraclete, literally means he who is at one's side, ad vocatus in Latin, our heavenly Perry Mason. For those of us who are older, maybe remember who Perry Mason is. In the court of opinion, in the world's opinion, the Son sends us the Spirit as our defense. So, the Holy Spirit's job will be one, to defend the faithful in their witness to Jesus Christ.
Our Lord at the Last Supper said the Holy Spirit would be with the disciples forever, he said in John 14:16. He said the Holy Spirit would teach the disciples all things and help them to remember everything that Jesus had told them, John 14:26. And that he would essentially defend them against who, against the accuser, known as the devil, whom St. John says in Revelation 12:10 accuses the brethren day and night before God. So, the Holy Spirit defends us, instructs us, he reminds us of our Lord's words and his teachings.
But secondly, he also sanctifies us. It's his job to make our Lord visible once again on the earth, but visible specifically through us. If others see Jesus in us, that means that we are cooperating with the Holy Spirit's work in us. And thirdly, the Holy Spirit will not only sanctify and defend us, but he'll also convince or convict the world, says St. John in John 16:8. He will turn from being our defender to being the unbelieving world's prosecutor.
The Catechism at number 729 echoes the words of today's gospel, saying that the Holy Spirit will prove the world wrong about sin, about righteousness, and about judgment. So, first to us, the Holy Spirit enlightens us, helps us to understand that the world's views regarding what's right and wrong are usually backwards in our Lord's eyes. The Holy Spirit will also convict unbelievers. He will help them to see that what they think is wrong, for example, being a faithful Catholic, they think that's wrong, he'll make them see that that's actually the right way to live.
Regarding righteousness, the Holy Spirit will make sinners see how unrighteous they really are. So, he takes away the self-righteous glasses off of their eyes and helps them to see that they're not so righteous after all, and that really only our Lord is truly righteous. And regarding judgment and condemnation, the Holy Spirit will show unbelievers that Satan, the prince of this world, is the one to be condemned, not faithful Christians, and certainly not our loving Savior.
As Pope Leo XIV said in his first public address on May 8th, he said, "God cares for us, God loves all of us, and evil will not prevail." We are all in God's hands. Evil will not prevail. Why will it not prevail? Because Jesus has given us the Holy Spirit, the Holy Spirit as our defender, our sanctifier, and our guide.
Lastly, we can't end without noting that not only is the Holy Spirit our counselor, our advocate, St. John also says that Jesus is our paraclete as well, that he's our advocate with the Father, he says that in 1 John 2:1. And yes, we also call our Blessed Mother our advocate as well. We say, every time we say or sing the Salve Regina in Latin, we call her Advocata Nostra: "Turn then, most gracious advocate, thine eyes of mercy toward us." So, we have three expert lawyers with us and on our side: Jesus, Mary, and the Holy Spirit. All we have to do is cooperate with them, and they will lead us to the freedom of our heavenly homeland where our Lord is preparing a place for us as we speak.
So, let's ask Our Lady in particular for the grace to be faithful witnesses to her Son, no matter what situation we find ourselves in. 
And praised be Jesus and Mary, now and forever.