‘Howsoever beyond imagination may the vibrations of bliss be, their soothing effect itself will make them burst forth, sometime or the other.’

Implied meaning:

    The vibrations of bliss are beyond one’s imagination, because an average person has not experienced spiritual happiness or inner bliss. He has only experienced the happiness of day-to-day life.

    ‘Their soothing effect will make them burst forth, sometime or the other’, means that every being has a natural urge to experience bliss; hence, the thought of attaining bliss does surface at some time or the other.