Spirits and angels have memory just as we do. What they hear and see and think and intend and do stays with them; and through their memory they are constantly developing their rational ability forever. This is why spirits and angels are being perfected in intelligence and wisdom through experiences of what is true and good just the way we are.
I have been shown that spirits and angels have memory by a great deal of experience as well. I have seen everything they had thought and done called up from their memory both in public and in private, when they were with other spirits. I have also seen people who had been focused on some truth from simple virtue become steeped in insights and in a consequent intelligence and then taken up into heaven.
It should be realized, though, that they are not steeped in insights and a consequent intelligence beyond the level of the affection for what is good and true that engaged them in the world. In fact, each spirit and angel retains the amount and kind of affection she or he had in the world, and this is afterward perfected by being filled in. This too goes on forever, since everything is capable of infinite variation and enrichment by different means, so it can be multiplied and can bear fruit. There is no end to any instance of goodness, since its source is the Infinite.
The fact that spirits and angels are constantly being perfected in intelligence and wisdom by means of insights into what is true and good has been presented in the chapters on the wisdom of heaven’s angels (Sections 265–275); on non-Christians or people outside the church in heaven (Sections 318–328); and on infants in heaven (Sections 329–345). This happens at the level of the affection for the good and the true that engaged them in the world, and not beyond it (Section 349).
from Heaven and Hell, Section 469
Sections 265-275: Published 10/18/2017-10/24/2017
Sections 318-325: Published 7/17/2017-7/23/2017
Sections 329-345: Published 7/9/2018-7/17/2018