Knowing one’s own (spiritual) poverty, that is strength.
Not knowing one’s own spiritual poverty is a shortcoming.
It is a spiritual sickness if one lives with a shortcoming without knowing it.
Most people live in sickness and they don’t know they are sick.
The sage is not sick, because he knows it is sickness if one doesn’t know his own poverty.
The sage knows he is poor before God because he knows very little about true (divine) knowledge.
Implications from the Holy Books
We have forbidden men to walk after the imaginations of their hearts, that they may be enabled to recognize Him Who is the sovereign Source and Object of all knowledge, and may acknowledge whatsoever He may be pleased to reveal. Witness how they have entangled themselves with their idle fancies and vain imaginations. By My life! They are themselves the victims of what their own hearts have devised, and yet they perceive it not. Vain and profitless is the talk of their lips, and yet they understand not. ── Bahá’u’lláh, Gleanings From the Writings of Bahá’u’lláh 100
O my God! I testify that no thought of Thee, howsoever wondrous, can ever ascend into the heaven of Thy knowledge, and no praise of Thee, no matter how transcendent, can soar up to the atmosphere of Thy wisdom. From eternity Thou hast been removed far above the reach and the ken of the comprehension of Thy servants, and immeasurably exalted above the strivings of Thy bondslaves to express Thy mystery. What power can the shadowy creature claim to possess when face to face with Him Who is the Uncreated? ── Bahá’u’lláh