The blessing (salat) which God sends upon His Beloved is His love and affection for him, and His drawing him nigh and electing him; and the peace (salam) He sends him is a salutation and generous ennoblement, and an expression of utmost kindness and favour.
In the invocation of blessings upon the Messenger of God (upon whom be blessings and peace), people are divided into three groups:
First there are those who send blessings upon his human form; these are the people of rational arguments and proofs. They envisage him in their hearts as they invoke blessings upon him, and as they invoke more and more (with presence of mind), the noble image becomes firmer and firmer in their hearts. Thus they see him often in their dreams; and perhaps his noble spirit might take the form of his blessed body so that they see him in a waking state.
Then there are those who invoke blessings upon his illuminating spirit; these are the people of witnessing who travel the spiritual path. They invoke blessings upon his light which flows down from the Realm of Domination (al-Jabarut), and they witness him most of the time, as long as they have presence of mind and vision.
Then there are those who invoke blessings upon his primordial light, which is the light of all lights; these are the people of spiritual firmness and mastery, they of direct witnessing and vision. The Prophet (upon whom be blessings and peace) never leaves them for a moment, which is why Sheikh Abu Abbas [al-Mursi], God be pleased with him, said: ‘Were the Messenger of God (upon whom be blessings and peace) to leave me for the blinking of an eye, I would no longer count myself a Muslim.’ In saying this he was alluding to his own firmness and mastery in the Presence, and his having come back to the station of subsistence (al-baqa) wherein one witnesses the Intermediary. Such people’s thoughts roam through the World of Dominion (al-Malakut), and their spirits are connected to the World of Domination (al-Jabarut), and in them is synthesised all that is lacking in others, as the Prophet (upon whom be blessings and peace) said: ‘All prey is in the belly of the wild donkey’; for the wild donkey is the fattest of all hunted animals, so that whoever catches one is as fortunate as he would be to catch them all. And the poet said:
It is not beyond God in the least
To combine all worlds in one man.
(From al-Futuhat al-Ilahiyyah.)