Lie #1) Israel is only targeting legitimate military sites and is seeking to protect innocent lives. Israel never targets civilians.
The Gaza Strip is one of the most densely populated pieces of property in the world. The presence of militants within a civilian population does not, under international law, deprive that population of their protected status, and hence any assault upon that population under the guise of targeting militants is, in fact, a war crime.
Lie #2) Hamas violated the cease-fire. The Israeli bombardment is a response to Palestinian rocket fire and is designed to end such rocket attacks.
Israel never observed the cease-fire to begin with. From the beginning, it announced a “special security zone” within the Gaza Strip and announced that Palestinians who enter this zone will be fired upon. In other words, Israel announced its intention that Israeli soldiers would shoot at farmers and other individuals attempting to reach their own land in direct violation of not only the cease-fire but international law.
More "Top 5 Lies About Israel’s Assault on Gaza" by Jeremy R. Hammond on Foreign Policy Journal