Perhaps he had already encountered Jesus. Perhaps it was his very relationship with Jesus which led him to search for truth.
If this was a conversion from paganism or atheism to Christianity, then I would agree with you. In that case, a man would go from unbelief to belief. From darkness to light. From ignorance of Jesus to faith in Jesus.
However, this man was already a believer. He likely already accepted the death and resurrection of Jesus Christ, the reality of heaven, hell and the Holy Trinity. He was looking for the fullness of truth.
What, exactly, does this mean to a RC?