June 7

…Bahá’u’lláh departed His House in Baghdad for the Najíbíyyih Garden, where He would, for the first time, openly disclose His prophetic mission. He left behind Him an edifice of surpassing sacredness that had sheltered Him for seven years. This sanctified residence, to which the Blessed Beauty would never return, was styled by Him the “Most Great House”; designated, along with the House of the Báb in Shiraz, as the place of Bahá’í pilgrimage; and addressed, by the Supreme Pen, in these stirring words:

“I testify that thou art the scene of His transcendent glory, His most holy habitation. Out of thee hath gone forth the Breath of the All-Glorious, a Breath that hath breathed over all created things, and filled with joy the breasts of the devout that dwell in the mansions of Paradise.” 
- The Universal House of Justice  (From a letter dated 17 July 2013)