As Catholics, we believe that we are both body and spirit, and it is the unity of body and spirit that defines our humanity.
"The body, and it alone is capable of making visible what is invisible, the spiritual and divine. It was created to transfer into the visible reality of the world, the invisible mystery hidden in God from time immemorial, and thus to be a sign of it.”
---St. John Paul II---
This truth can be seen no more fully and perfectly than through Christ’s incarnation (God assuming a human nature in order to accomplish our salvation in it).
“And the Word became flesh and made his dwelling among us, and we saw his glory, the glory as of the Father’s only Son, full of grace and truth.”
This truth can also be seen every day. When parents embrace their children, we can see both a visible and invisible reality. The visible reality we see is the embrace. The invisible reality the embrace reveals is love. We cannot "see" the love the hug expresses, though sometimes we can see its nurturing effect in the child. In the same way, the Sacraments have a visible and invisible reality. The Sacraments themselves are carried out physically (visibly); whereas the grace received through the Sacraments cannot be seen (it is invisible).
We believe Christ instituted seven sacraments: Baptism, Confirmation, the Eucharist, Penance, the Anointing of the Sick, Holy Orders, and Matrimony.
“The seven sacraments touch all the stages and all the important moments of Christian life: they give birth and increase, healing and mission to the Christian’s life of faith. There is thus a certain resemblance between the stages of natural life and the stages of the spiritual life.”
---The Catechism of the Catholic Church, no. 1210---