Both days are celebrated in great majority of Muslim countries with sizeable Christian minorities like Pakistan, Indonesia, Iran, Nigeria, Egypt, Lebanon, etc. Christmas is a national holiday in those countries but not the Easter.
Unlike the so-called ‘civilized West’, mocking of Jesus or his mother Mary is considered blasphemy among the Believers of all Schools of Islamic Thoughts (Hanafi, Maliki, Shafi’i, Hanbali, and Ja’fri).
The great majority of Muslims, however, don’t celebrate Easter or Christmas the way Christians do due to Holy Qur’an’s narrative of the birth and the end of prophet Jesus’ (as) life on Earth.
“That they (Yahud and Nasara) boast, “We killed Christ Jesus the son of Mary, the Messenger of Allah – but they killed him not, nor crucified him, but so it was made to appear to them, and those who differ therein are full of doubts, with no (certain) knowledge, but only conjecture to follow, for of a surety they killed him not,” Holy Qur’an (4:157).
“Nay, Allah raised him up unto Himself; and Allah is Exalted in Power, Wise,” Holy Qur’an (4:158).
Thus Holy Qur’an clearly states that Jesus (as) was never put on cross, or died on cross or resurrected afterward. Holy Qur’an also asserts in other places that both Torah (OT) and Ingeel (NT) were corrupted by their authors and revisionists. Robert W. Funk, renowned authority on the New Testament agrees with that in his book The Five Gospels.
There are several other beliefs on which Islam doesn’t agree with Christianity. However, both faiths believe in virgin birth of Jesus, his ascend to Heaven and his second-coming. But, the purpose of his second-coming, according to Holy Qur’an is not to force conversion of Jews to Christianity (as believed by 80 million Evangelists), but as a Muslim to bring peace on Earth and to die a natural death afterwards.
Personally, I think a Muslim, who joins his Christian friends or relatives in Easter celebration, is not committing an un-Islamic act.
Happy Easter, everyone!