To deepen in the Cause means to read
the Writings of Bahá'u'lláh and the Master so thoroughly as to be able to give
it to others in its pure form. There are many who have some superficial idea of
what the Cause stands for. They, therefore, present it together with all sorts
of ideas that are their own. As the Cause is still in its early days we must be
most careful lest we fall under this error and injure the Movement we so much
adore. There is no limit to the study of the Cause. The more we read the Writings,
the more Truths we can find in Them, the more we will see that our previous
notions were erroneous.
(From a letter dated 25 April 1926 written on
behalf of Shoghi Effendi to an individual believer; The Compilation of
Compilations, vol. I, The
Importance of Deepening Our Knowledge and Understanding of the Faith)