They don't it is a Jewish celebration.
Although some Christians can choose to reference Passover, they do not celebrate the actual Jewish holiday of Passover. The main reason being that the beliefs of Christianity are diametrically opposed to the meaning behind Passover. Christians celebrate the holiday of Easter which occurs at the same time of year as Passover (although the two holidays are completely unrelated).
Yes. Some Christians celebrate Passover as the Jews celebrate it. They roast and eat lamb, bitter herbs, and unleavened matzo. Others follow the instructions that Jesus gave to his disciples at the Last Supper before he was crucified, and share bread (usually unleavened) and wine instead of roasted lamb.
no, these are 2 entirely different celebrations that were hundreds of years apart.
no, these are 2 entirely different celebrations that were hundreds of years apart.
The passover is a festival celebrated by the Jews, it reminds them of the night when they were slaves in Egypt, and they smeared the blood of lambs on the doors and in the night, the angel passed the houses. Those that did not have the blood , had their first born died.
Christians can eat whatever they wish during the 8 day holiday of Passover. Although Passover is a Jewish holiday, Christians also acknowledge it.
Yes, because Passover is a Jewish festival. see also:What_do_Jews_do_when_celebrating_passover
Non-Jews are not commanded to remember or observe Passover. Jews are commanded to remember and keep Passover (Exodus ch.12), and they should do so.
There are always Jews who celebrate Passover regardless of the location or circumstances. Jews celebrated Passover in the ghettos, and then in the concentration camps.
yes
Irish Jews celebrate Passover the same way as Jews all over the world.