IN EVERY SINGLE EUROPEAN LANGUAGE EXCEPT ENGLISH, Pascha/Paschal means easter. Even originally in German it was Paschen.
Pesach and Paschen or Pascua, Paschal, Pascha are linguistically the same word.
As stated FROM THE NEW TESTAMENT, we are commanded to keep Pesach in memory of our savior's death.
We do though the high(-est Christian) holiday of Easter, i.e. Paschen.
From the Op: "He commands us to observe his death, by keeping the Passover as shown in Matthew 26: 26-30, and John 13:1-17. "