Graham Greene always believed that at a point in a child's life, an experience takes place that changes the child in a major way.
This is clearly seen in 'The Hint of an Explanation', a dialogue between a child and a man (who we realize is a priest at the end), who recounts a childhood experience, which to him, contains a 'hint' that God exists. As a child, he used to serve at the mass, which was a 'routine like drill', never taken seriously, and only a cause of embarrassment. This was soon to change. Blacker, a local baker, bribes him to get a consecrated host. The boy realises that his action would be sinful; 'I didn't want to play with the train any more that day', he says. However, he obeys Blacker out of fear. When the boy gets the host and inserts it between two sheets, he describes the host as a 'little damp mess of pump'.
It had little value to him. Later that night, however, he realizes the severity of his actions. In his room, he is 'haunted by the presence of God there on the chair'. What once was a lump of pulp, is now God, 'something of infinite value'. No fear could stop his belief, and his ultimate act of faith when he swallows the host, the body of Jesus. A child, who was indifferent about God, now realizes the value of the Host. This experience, this 'hint', led to his becoming of a priest.
One can also see this complete change in character in 'I Spy'. This is a story about a child, Charlie Stowe, who goes down to his father's tobacco shop to smoke for the first time. At first, we are told that Charlie 'did not love his father',