1) Jesus brought a new covenant, so yes we ignore the stuff from the old testament.
2) Jesus was using a metaphor. There are tons of them in the bible (did you know the Kingdom of God isn't literally a mustard seed?! Huh!). You'll notice also HE brought the (metaphorical) sword. He did not give it to his followers, and he never used it. He strictly forbade his followers from using the physical sword.
Now tell me how many people Mohamed murdered and crucified? This is the horror of multiculturalism: you cannot tell the difference between christianity and its exact opposite islam.
Because of this, the Mohammedans, who do not give a shit about your whiny multicultural bullshit will behead you and rape your women. I'll be fine though. Even in ISIS lands they're not killing Christians so long as they pay the jizya.