All of these Names are close in meaning and all of them point to describing the Lord with mercy, generosity and kindness. They point to the great expanse of His mercy and gifts that encompass all that is existence, being granted in accordance to the dictates of His wisdom. The believers have been specifically singled out for this and they are granted a goodly and the best portion of this. All blessings and the various aspects of beneficence are from the effects of His mercy, generosity and kindness just as all beneficence in this world and in the Hereafter is from the effects of His mercy.
“My mercy encompasses all things and I shall decree it for those who have taqwa.”
[al-A'raf (7): 156]
“Verily, we used to call on Him [Alone] before. Verily He is al-Barr, ar-Rahim.”
[at-Tur (52): 28]
From “Explanation to the Beautiful and Perfect Names of Allah” — Shaykh as-Sa’di (d.1376H)