This song was written by Jonathan Chazak and is said to be linked to the story of the poor fisherman who catches a fish for Shabbat and on opening it discovers precious jewels. The lesson is that we should always make an effort to buy special items for Shabbat as we will be rewarded for doing so.
The song covers the importance of having good food and wine for Shabbat, keeping the commandments and really resting on the Shabbat.