Jerome : "And he brought me into the porch of the temple, and he measured the porch five cubits on this side, and five cubits on that side: and the breadth of the gate three cubits on this side, and three cubits on that side." Moreover, the aforementioned man led Ezekiel into the vestibule, or πρόπυλον of the temple, which measured five cubits on each side, for the one who was brought in had been trained in divine understanding and knew neither right nor left, but entered by the royal way. The width of the gate itself, which was the entrance to the vestibule of the temple, was three cubits on each side. In the elegant observance of the Holy Scriptures, it is not said from the right or the left, lest anything be named left in the Holy of Holies, but from this side and that side, that is, from both sides. And immediately the discerning reader understands that the number three relates to the mystery of the Trinity, which is the gate for those who approach God, for the Father is in the Son, and the Son is in the Father, and the Holy Spirit is in both. This number three is the gate for those who, after baptism in the Trinity, come to salvation. — Commentary on Ezekiel