Now that it has been deciphered - it has been revealed that these were curses engraved on stone against the ruler in Jerusalem from the middle or late Bronze Age. 

Gershon Galil, who deciphered the text: The inscription consists of 20 words in the ancient Proto-Canaanite script

The unique stone slab was discovered as part of archeological excavations conducted in Jerusalem more than a decade ago. Now that the inscription in the center of the board has been deciphered, it turns out that it bears the words "cursed," "dead," and "die!"

Source: N12 News