"all good and all evil come to us through sensation".
Let's begin with context. If I'm not mistaken, this quote comes from Locke. This passage from the letter to Menoikeus is, I think, the closest equivalent in Epicurean philosophy.
"Second, train yourself to hold that death is nothing to us, because good and evil consist in sensation, and death is the removal of sensation. A correct understanding that death is nothing to us makes the mortality of life enjoyable — not because it gives you an unbounded span of time, but because it removes the desire for immortality. There is nothing terrifying in life to someone who truly understands that there is nothing terrifying in the absence of life."
There is a difference in nuance between these two quotations which shows some further points of discussion. Epicurus' quote is in the context of discussing why we shouldn't fear death; I'm not aware of the context of Locke's quote.