Do you want to know what goes on in the heart of the Trinity? I will tell you. In the heart of the Trinity the Father laughs and gives birth to the Son. The Son laughs back at the Father and gives birth to the Spirit. The whole Trinity laughs and gives birth to us.
When God laughs at the soul and the soul laughs back at God, the persons of the Trinity are begotten. When the Father laughs at the Son and the Son laughs back at the Father, that laughter gives pleasure, that pleasure gives joy, that joy gives love, and that is the Holy Spirit.