III. The Love of Husband and Wife

2366
Fecundity is a gift, an end of marriage, for conjugal love naturally tends to
be fruitful. A child does not come from outside as something added on to the
mutual love of the spouses, but springs from the very heart of that mutual
giving, as its fruit and fulfillment. So the Church, which “is on the side
of life”¹⁵⁰ teaches that “each and every marriage act must
remain open ‘per se’ to the transmission of life.”¹⁵¹ “This
particular doctrine, expounded on numerous occasions by the Magisterium, is
based on the inseparable connection, established by God, which man on his own
initiative may not break, between the unitive significance and the procreative
significance which are both inherent to the marriage act.”¹⁵²

From The Catechism of the Catholic Church – rosary.team

Original Link: https://www.vatican.va/archive/ENG0015/__P86.HTM