While Hamas was unilaterally engaging in a cease fire, Israel had continued bombing occupied Palestine and had killed quite a few civilians as well as Hamas members in their campaign of assassinating Hamas members.

I will put this another way. Israel did not participate in that cease fire. Only Hamas did. Israel kept on killing and assassinating Palestinians civilians and members of Hamas during that period. Hamas demonstrated that they are capable of doing what they say they will do, and they demonstrated that they can be trusted to not engage in any violent acts when they say this is what they will do. What Israel demonstrated during this time is that violence from Hamas is not the reason for anything that Israel does to the Palestinians. It's just an excuse for things they would do, and have done, even in the absence of violence from Hamas.