Some modern versions interpret this phrase as "as a memorial to the generosity of the son of Zephaniah" or "as a memorial to the one who is gracious, the son of Zephaniah." Also, some modern versions interpret the name "Hen" as meaning the name "Josiah."
Here to "listen" means to obey and the word "voice" represents the words that Yahweh speaks. AT: "truly obey what Yahweh your God says" (See: [[rc://en/ta/man/translate/figs-metonymy]])