Acharya Prashant explains that conditioning occurs when the mind receives external influences through the senses without understanding them. He emphasizes that anything understood deeply ceases to be a foreign influence and becomes one's own fresh understanding, much like how Newton's laws belong to the universe rather than Newton once they are understood. Conversely, whatever is not understood remains a layer of conditioning that makes the mind heavy. He asserts that alertness and energy are required during listening to prevent the speaker's words from becoming mere conditioning.