Bahá’í Sacred Writings, Bahá’u’lláh, #130
And now concerning thy question whether human souls continue to be conscious one of another after their separation from the body. Know thou that the souls of the people of Bahá, who have entered and been established within the Crimson Ark, shall associate and commune intimately one with another, and shall be so closely associated in their lives, their aspirations, their aims and strivings as to be even as one soul. They are indeed the ones who are well-informed, who are keen-sighted, and who are endued with understanding. Thus hath it been decreed by Him Who is the All-Knowing, the All-Wise.
The people of Bahá, who are the inmates of the Ark of God, are, one and all, well aware of one another’s state and condition, and are united in the bonds of intimacy and fellowship. Such a state, however, must depend upon their faith and their conduct. They that are of the same grade and station are fully aware of one another’s capacity, character, accomplishments and merits. They that are of a lower grade, however, are incapable of comprehending adequately the station, or of estimating the merits, of those that rank above them. Each shall receive his share from thy Lord. Blessed is the man that hath turned his face towards God, and walked steadfastly in His love, until his soul hath winged its flight unto God, the Sovereign Lord of all, the Most Powerful, the Ever-Forgiving, the All-Merciful.
The souls of the infidels, however, shall—and to this I bear witness—when breathing their last be made aware of the good things that have escaped them, and shall bemoan their plight, and shall humble themselves before God. They shall continue doing so after the separation of their souls from their bodies.
It is clear and evident that all men shall, after their physical death, estimate the worth of their deeds, and realize all that their hands have wrought. I swear by the Day-Star that shineth above the horizon of Divine power! They that are the followers of the one true God shall, the moment they depart out of this life, experience such joy and gladness as would be impossible to describe, while they that live in error shall be seized with such fear and trembling, and shall be filled with such consternation, as nothing can exceed. Well is it with him that hath quaffed the choice and incorruptible wine of faith through the gracious favour and the manifold bounties of Him Who is the Lord of all Faiths.