The following quotes and paraphrases are from Yampolsky's translation of a letter by Hakuin Zenji.
"[When I was 16 years old I noticed the great veneration people had for the Lotus Sutra.] There must indeed be profound and mysterious doctrines in this sutra. . . . . But in my study of it I found that . . . the text was [mostly] concerned with parables relating to cause and effect. . . .Why should this particular sutra be so highly esteemed? My hopes were completely dashed."
"[When I was 40 years old] I took up the Lotus Sutra [again]. Suddenly I penetrated the perfect, true, ultimate meaning of the Lotus. The doubts I held initially were destroyed and I became aware that the understanding I had attained up to then was greatly in error. Unconsciously I uttered a great cry and burst into tears."