In the Gospel Reading, Christ explains why he speaks in parables to the crowds. The knowledge of these things has been granted to you, Christ tells his disciples, but it hasn’t been granted to them.
But if God can give the gift of knowledge, why wouldn’t he give it to everyone? Why would a loving God hide knowledge from some people?
To see the answer, think about gifts. If you give a gift to someone you love, then what you give is intended to do that person good. It isn’t a gift if what you are giving will harm him or hurt him, and you know that it will.
And that is why Christ speaks in parables. Among those who come to him, there are some people who want to hear him but are not willing to be counted among his disciples, at least not yet. Christ’s parables give those people what they can receive, given that they are not yet ready to receive him. They can learn something from the parables even so.
But to those who come to Christ ready to receive him and willing to be counted as his disciples, he can give the gift of knowledge straightforwardly. In receiving him, those people are also ready to receive the knowledge Christ can give.
And here it is worth noticing that Christ speaks in parables to everybody who comes to him. But some people care enough about him and his words to want more than they can get from those parables alone. They take him as their teacher and want to learn from him. That is why they come to him to ask him to explain the parables he was telling them as well as all the others. The people who want more understanding are the people who count as his disciples.
As Christ says, to them who have more, because they want more, more will be given.