Trust plays a big role in our spiritual lives, especially whenever we pray to God.
Intercessory prayer in particular is a primary way our trust in God is tested.
The Catechism of the Catholic Church introduces this topic in its section on prayer:
Filial trust is tested -- it proves itself -- in tribulation. The principal difficulty concerns the prayer of petition, for oneself or for others in intercession.
Whenever we pray for something or someone, we should ask ourselves, "Do I believe that God will answer my prayer?"
A similar question to ask ourselves is, "Do I trust in God's faithfulness?"
If we are honest with ourselves, most of the time we pray and don't truly believe that God is going to answer our prayer.
This disposition is often affected by our past experiences, especially when we pray for someone's healing and they are not healed.
We may think to ourselves that God didn't answer our prayer, because he didn't heal that person or didn't hear us when we prayed.
When faced with apparent "silence," we can be tempted to stop praying, as we think that God didn't hear us.
Does God hear our prayers?
The Catechism similarly expresses this difficulty that many of us experience:
Some even stop praying because they think their petition is not heard. Here two questions should be asked: Why do we think our petition has not been heard? How is our prayer heard, how is it "efficacious"?
The key point to keep in mind is that God always hears our prayers. If we truly believe that God exists and that he is present to us in every moment of our lives, there is no possible way that he could be "deaf" to our prayers.
God hears every person's prayer, no matter who they are or what language they speak.
For many of us, the disappointment is when God answers our prayers in a way that we don't like.
God may not heal someone for a specific reason, though we likely won't know that reason before we die.
What we need to do is trust that God's ways are always better for us in the end.
God knows us better than we know ourselves. We just need to trust him.