According to the Israel Ministry of Foreign Affairs, in honor of Pope Francis’ visit, President Rivlin gave him a copy of what appears to be the Tel Dan Stele — the inscription that famously mentions the “House of David”.

From the article:
The gift was chosen in particular as an expression of the deep roots shared by Judaism and Christianity, and as King David is regarded by both Judaism and Christianity as the founder of the House of David, revered in tradition as being from which would come the redemption of humanity, and from whom the Messiah would be descended.
Peace,
-Steve