I believe the correct answer is: It implies that in order to
reach salvation, one need to have a helper, like Hopeful.
The archetype of a journey across
water, which represents hero's purification, has the same effect of
purification for Christian's crossing of the river in “Pilgrim's Progress” (1678), a Christian allegory
written by John Bunyan, but in religious context:
“Christian doubts whether he can
make it across, for the memory of his past sins weights on him one again, but
Hopeful reminds him that Christ’s love would take away those sins.”
This allegory implies that in order to reach salvation, one
need to have Hope. The Hope is one of three pillars of Christianity, alongside
Love and Faith. In the final part, it’s implied that only true hope and belief
can preserve one on his journey to Heaven, but the Vain Hope cannot:
“Ignorance has crossed the river on a ferry called Vain Hope,
and yet he will not be admitted to the Celestial City, because he doesn’t have
a scroll-ticket.”
