This testimony of our Savior is clear, and it states exactly and in an admirable manner what we read in the Book of Wisdom (1:4). It is indeed the three divine persons who come and dwell in the souls of the just.

Thus the apostles understood it. St. John writes: “God is charity: and he that abides in charity, abides in God, and God in him”.

He possesses God in his heart; but still more God possesses him and holds him, preserving not only his natural existence, but the life of grace and charity in him.

St. Paul speaks in like manner: “The charity of God is poured forth in our hearts, by the Holy Ghost who is given to us”.

We have received not only created charity, but the Holy Ghost Himself who has been given to us. St. Paul speaks of Him especially, because charity likens us more to the Holy Ghost, who is personal love, than to the Father and to the Son.

They are also in us, according to the testimony of Christ, but we will be made perfectly like Them only when we receive the light of glory, which will imprint in us the resemblance to the Word, who is the splendor of the Father.

On several different occasions St. Paul refers to this consoling doctrine: “Know you not that you are the temple of God, and that the Spirit of God dwells in you?”

“Or know you not that your members are the temple of the Holy Ghost, who is in you, whom you have from God; and you are not your own? For you are bought with a great price. Glorify and bear God in your body”.

Scripture thus teaches explicitly that the three divine persons dwell in every just soul, in every soul in the state of grace.

R. Garrigou-Lagrange OP (1877-1964): The Three Ages of the Interior Life