He wanted to strike because of his "hatred of Jews." From [1] Israel National News, with thanks to Sr. Soph:

A 20-year-old Palestinian arrived Saturday morning at the 300 roadblock south of Jerusalem. Border Guard police officers searched him and discovered that he was carrying two ready-to-use improvised explosive devices, a plastic gun and a knitted hat. The devices included explosives and nails. Sappers, who were dispatched to the area, detonated the charges in a controlled manner. The Palestinian, a resident of the village of Abadia near Bethlehem, was detained and taken into investigation. In his investigation, the young man said that he had planned on carrying out a terror attack in Jerusalem, claiming that he wanted to do so because of his "hatred of Jews."