To be open to life means let God, in his lovingly providence, determine the number of children each family is called to educate. The ones who defend this idea nowadays are called, at least, crazy or irresponsible, because we live in a culture totally against life. However, since this idea is the true doctrine of the Catholic Church and really represents God’s plan for marriage and the family, it is worthy to fight to assume this truth in our lives.
The first step is to convince ourselves that God really asks to every couple to surrender their fertility into his loving and provident hands, leaving in his charge the number of children they shall bring to this world. To do that, we can study the encyclical Humanae Vitae, especially number 10; the pastoral constitution Gaudium et Spes, number 50, the recent apostolic exhortation Amoris Laetitia, numbers 14 and 84, and Life-giving Love, an excellent book by Kimberly Hahn.
Then we need to mature our faith in Divine Providence; that is, to manage to really feel that God is Father who loves us infinitely and will not allow that we have more children than we can raise properly. Trust, trust and trust. And we only grow in trust by trusting: intensifying our prayer life, the practice of meditation where we deepen our knowledge about God’s love for us, attending the sacraments, especially Eucharist and Confession. It also helps to hear the testimony of large families that practice this teaching. Believe me, they are not so hard to find; you just have to look for them a bit!
Well, here comes the greatness of the Church, that is not only Teacher, but mostly Mother. She knows that God doesn’t demand more than each one can bear. For each person, God asks for a different level of heroism. Therefore, everybody is called to blindly trust in Divine Providence, but not all manage to do that immediately and need more means to walk in that direction. So, when there are serious reasons to postpone a pregnancy, it is permitted for the couple to use the infertile days for sexual relations and therefore expect, in a natural way, for pregnancy not to happen.
I also believe that natural methods (NFP) can be a way to get to the total openness to life. It can happen that a couple doesn’t manage, abruptly, to stop using contraceptives and surrender their fertility into God’s hands. So they can start using NFP, still postponing a pregnancy, because, at least they wouldn’t be putting any physical or chemical barrier in their sexual relations. They would be already giving themselves fully to each other.
With time, reflecting each cycle about whether they really have serious reasons to postpone a pregnancy, the couple may grow in the filial trust in the Divine Providence and reach the conclusion that they don’t need more graphs or charts anymore and they can celebrate their love without major concerns.
It is important to have in mind that to be open to life does not mean that you will have many children. Fertility is a very fragile gift and it varies a lot during your life. I know couples that never used contraception and have only 2 or 3 children, or even none! Another factor is that nowadays people are getting married older, around 30 years old, which greatly decreases the number of children that they can naturally conceive. So there is nothing to be afraid of!
We should always try to do God’s will and trust that he will do everything perfectly well, to our salvation and the salvation of our children!