Christ promised the apostles the Comforter, the Spirit. Let us see how He promised Him. 'If you love Me,' He says, 'keep My commandments. And I will pray the Father, and He will give you another Comforter, that He may abide with you forever, the Spirit of truth' (Jn 14:15-16). This is certainly the Holy Spirit in the Trinity. The catholic faith confesses Him to be consubstantial and coeternal with the Father and the Son.
Of Him the Apostle says: 'The love of God has been poured into our hearts through the Holy Spirit, who has been given to us' (Rom 5:5). How then does the Lord say, 'If you love Me, keep My commandments. And I will pray the Father, and He will give you another Comforter'? For it is said of the Holy Spirit that, without Him, we can neither love God nor keep His commandments.
How can we love, in order to receive Him, if without Him we cannot love? Or how shall we keep His commandments, in order to receive Him, if without Him we cannot keep them? Or perhaps there is first in us a love by which we love Christ. Then, through love for Christ and the keeping of His commandments, we are counted worthy to receive the Holy Spirit. Thus the love not for Christ, which is already in us, but for God the Father, would be poured into our hearts through the Holy Spirit given to us.
Such a judgment is perverse. Whoever believes that he loves the Son and does not love the Father certainly does not love the Son either, but imagines something for himself. Moreover, the apostolic words are these: 'No one says, Jesus is Lord, except in the Holy Spirit' (cf. 1 Cor 12:3). And who calls Jesus Lord, except one who loves Him, if he calls Him in the way the Apostle wished this to be understood?
Many say this with their lips, but deny it in heart and deeds. Of such the Apostle said: 'They profess to know God, but by their deeds they deny Him' (Tit 1:16). If they deny Him by deeds, then without doubt He must also be confessed by deeds.
Therefore no one says 'Jesus is Lord' with soul, word, deed, heart, and lips, except in the Holy Spirit. No one names Him so, except the one who loves Him. The apostles were already saying, 'Lord Jesus.' Since they named Him in such a way that they did not speak hypocritically, confessing with their lips while denying with heart and deeds, they certainly loved Him.
How, then, did they love Him, if not in the Holy Spirit? Yet they were first commanded to love Him and keep His commandments, in order to receive the Holy Spirit. Without Him they could neither love Him nor keep His commandments.
It remains for us to understand that one who loves already has the Holy Spirit. By having Him, he merits having Him still more. By having Him more, he merits loving more.
The disciples already had the Holy Spirit promised by the Lord, for without Him they would not have called Him Lord. Yet they did not yet have Him as the Lord promised Him. Thus they both had Him and did not have Him, since they did not yet have Him as fully as they were later to receive Him.
They had Him in small measure, but He would be given to them in greater measure. They had Him hiddenly, but would receive Him manifestly. For this belonged to the greater gift of the Holy Spirit, that it would become clear to them that they already had Him.
Mentioning this gift, the Apostle said: 'Now we have received not the spirit of the world, but the Spirit who is from God, that we might know the things given us by God' (1 Cor 2:12). The Lord also gave this manifest bestowal of the Holy Spirit not once, but twice.
Soon after He rose from the dead, He breathed and said: 'Receive the Holy Spirit' (Jn 20:22). Since He then gave Him, did He not later send Him, as He had promised? Or is it not the same Holy Spirit whom He then breathed and whom He later sent from heaven? (cf. Acts 2:4).
Why this bestowal of the Spirit, performed openly, was made twice is another question. Perhaps this twofold giving of the Spirit was done according to the two commandments of love, namely love of neighbor and love of God. In this way it would be made clear that love is the gift of the Holy Spirit.
If another explanation must be sought, we cannot now allow our discourse to enter such inquiries more deeply than is necessary. For now, let us acknowledge that without the Holy Spirit we can neither love Christ nor keep His commandments. The less we receive Him, the less we can do this. The more fully we receive Him, the more we can do it.
Therefore this promise is not in vain, either for one who does not have the Holy Spirit or for one who has Him. For one who does not have Him, it is so that he may receive Him. For one who has Him, it is so that he may have Him more fully.
If it were not true that one has Him less and another more, holy Elisha would not have said to holy Elijah: 'Let the Spirit that is in you be upon me twofold' (4 Kgs 2:9). When John the Baptist said, 'God does not give the Spirit by measure' (Jn 3:34), he was speaking properly of the Son of God. To Him the Spirit was not given by measure, because in Him dwells all the fullness of the Godhead (Col 2:9).
For the mediator between God and men, the man Christ Jesus, was not without the grace of the Holy Spirit (1 Tim 2:5). He Himself says that this prophecy was fulfilled concerning Him: 'The Spirit of the Lord is upon Me, because He has anointed Me and sent Me to preach good tidings to the poor' (cf. Lk 4:18).
That He is the Only-begotten Son, equal to the Father, belongs not to grace but to nature. That man was received into the unity of the Person of the Only-begotten Son belongs not to nature but to grace. The Gospel acknowledges and affirms this: 'The Child grew and became strong, being filled with wisdom, and the grace of God was upon Him' (Lk 2:40).
To others the Spirit is given by measure, and, being given, He is increased until He fills each one according to his measure and perfection. Hence the Apostle reminds us: 'Do not think of yourself more highly than you ought to think, but think soberly, according to the measure of faith which God has allotted to each' (Rom 12:3).
The Spirit Himself is not divided, but the gifts through the Spirit are divided. 'There are varieties of gifts, but the same Spirit' (1 Cor 12:4).
When He says, 'I will pray the Father, and He will give you another Comforter,' He reveals that He Himself is a Comforter. For Comforter, Paracletus, in Latin means advocate, advocatus. It was said of Christ: 'We have an advocate with the Father, Jesus Christ the righteous' (1 Jn 2:1).