The section of this sutta where the confused monk, after listening to the Buddha discourse on anatta, wonders " What self will experience the actions performed by not-self?" is similar to what many people new to the Dhamma struggle with.
Majjhimanikāya # 109. The Greater Discourse of the Full Moon Night
SuttaCentral
Monk, regarding any body – past, future, or present; internal or external; subtle or not subtle; inferior or superior; far or near – using correct wisdom, one accurately sees every body in this way: ‘This is not mine, I am not this, this is not my self.’ Regarding any feeling… recognition… thought… consciousness – past, future, or present; internal or external; subtle or not subtle; inferior or superior; far or near – using correct wisdom, one accurately sees every consciousness in this way: ‘This is not mine, I am not this, this is not my self.’ Monk, knowing and seeing in this way, there is no I-making, my-making, or tendency towards conceit as regards this body, its consciousness, and all external appearances.”Then this line of thought arose in the mind of a certain monk: “Apparently the body is not self, feeling is not self, recognition is not self, thoughts are not self, and consciousness is not self. What self will experience the actions performed by not-self?”
Then the Blessed One, after reading the thoughts of that monk, addressed the monks: “Monks, it is possible that some foolish man here who has not understood, who is immersed in ignorance and dominated by craving, might think to override the Teacher‘s instructions by thinking, ‘Apparently the body is not self, feeling is not self, recognition is not self, thoughts are not self, and consciousness is not self. What self will experience the actions performed by not-self?’ Monks, I will question you about the teachings you have learned from me.
“What do you think, monks – is the body permanent or impermanent?”
“Impermanent, Bhante.”
“Is that which is impermanent a source of suffering or a source of happiness?”
“Suffering, Bhante.”
“Is it appropriate to regard that which is impermanent, a source of suffering, and subject to alteration as ‘This is mine, I am this, this is my self’?”
“Certainly not, Bhante.”
“What do you think, monks – is feeling… recognition… thought… consciousness permanent or impermanent?”
“Impermanent, Bhante.”
“Is that which is impermanent a source of suffering or a source of happiness?”
“Suffering, Bhante.”
“Is it appropriate to regard that which is impermanent, a source of suffering, and subject to alteration as ‘This is mine, I am this, this is my self’?”
“Certainly not, Bhante.”
“Therefore, monks, regarding any body – past, future, or present; internal or external; subtle or not subtle; inferior or superior; far or near – using correct wisdom, one accurately sees every body in this way: ‘This is not mine, I am not this, this is not my self.’ Regarding any feeling… recognition… thoughts… consciousness – past, future, or present; internal or external; subtle or not subtle; inferior or superior; far or near – using correct wisdom, one accurately sees every consciousness in this way: ‘This is not mine, I am not this, this is not my self.’ Monks, the educated disciple of the noble ones who sees in this way becomes disenchanted with the body, disenchanted with feeling, disenchanted with recognition, disenchanted with thoughts, disenchanted with consciousness. Disenchantment causes dispassion. Dispassion liberates. When liberated, there is the knowledge ‘Liberated.’ One understands, ‘Birth has been eliminated. The Holy Life has been consummated. What was to be done has been done. There will be no return to this state of existence.’”
This is what the Blessed One said. Satisfied, those monks delighted in the Blessed One‘s statement. While this explanation was being spoken, the minds of sixty monks were freed from the taints by means of non-clinging.