107 Bonaventure makes us appreciate first the beauty of the grace and the sacraments flowing from the fountain of life that is the wounded side of the Lord. “In order that from the side of Christ sleeping on the cross, the Church might be formed and the Scripture fulfilled that says: ‘They shall look upon him whom they pierced’, one of the soldiers struck him with a lance and opened his side. This was permitted by divine Providence so that, in the blood and water flowing from that wound, the price of our salvation might flow from the hidden wellspring of his heart, enabling the Church’s sacraments to confer the life of grace and thus to be, for those who live in Christ, like a cup filled from the living fount springing up to life eternal”.
Source: Dilexit Nos (Vatican.va)