Verily I say, this is the Day in which mankind can behold the Face, and hear the Voice, of the Promised One. The Call of God hath been raised, and the light of His countenance hath been lifted up upon men. It behoveth every man to blot out the trace of every idle word from the tablet of his heart, and to gaze, with an open and unbiased mind, on the signs of His Revelation, the proofs of His Mission, and the tokens of His glory.

Bahá'u'lláh
Gleanings From the Writings of Bahá’u’lláh, VII