3. Christ giving birth to the Church
The Church Fathers described the establishment of the Church as a second creation that was accomplished through the sacrifice of Jesus on Calvary. At that moment, water and blood flowed from the side of Christ, representing the waters of Baptism and the blood of the Eucharist or all the Sacraments, which gave birth to the Church and its individual members, as described by Paul. This event is also parallel to the creation of Eve from the side of Adam while he was asleep, with the difference that in the case of Eve the illuminators do not represent a wound in Adam's side and therefore during the birth of the first woman, which is an extraction of Eve from Adam's body, there is no blood. Instead, the Church is born out of the sufferings of Christ.
Through the sacrament of Baptism, each newly baptized person is embraced by Christ and incorporated into His Mystical Body, the Church. At the same time, Christ is embraced by each baptized person, as the Blessed Trinity indwells within them. This mutual embrace is like that between a husband and wife, with Christ holding us and us holding Christ, resulting in a union between man and God that fulfills the purpose of creation.
Vladimir Gurewich, Observations on the Iconography of the Wound in Christ's Side, with Special Reference to Its Position, in Journal of the Warburg and Courtauld Institutes , Jul. - Dec., 1957, Vol. 20, No. 3/4 (Jul. - Dec., 1957), pp. 358-362