In most of the Christian world, the day to celebrate our Lord's sacrifice, Good Friday, is scarcely noted, all the attention being on Easter. For those of us who are Messianic, while we also observe the true Resurrection Day, the Feast of Firstfruits, Passover is the main event, as it were. It is the ultimate Lord's Supper, containing not only the bread and the wine, but every element that the talmidim (disicples) would have had at their Last Seder: The bitter herbs (which Judas "outed" himself when dipping into; Mat. 26:23), the haroset (a sweet mixture of apple, herbs, and wine which resembles the mortar the Hebrews used to make bricks), the Lamb, etc.
There are a few questions that those not in the Messianic movement often ask. For example, "Can you find any evidence in the New Testament that the Christians kept the Passover?" You mean besides the Last Seder? Indeed, I can. In his first letter to the Corinthians, Sha'ul writes,
Your boasting is not good. Don't you know the saying, "It takes only a little hametz (leaven) to leaven a whole batch of dough?" Get rid of the old hametz, so that you can be a new batch of dough, because in reality you are unleavened. For our Pesach lamb, the Messiah, has been sacrificed. So let us celebrate the Seder not with leftover hametz, the hametz of wickedness and evil, but with the matzah of purity and truth. (1 Co. 5:6-8, CJB)One might argue, "Ah, but Paul meant that we should keep the Passover in a spiritual sense." I agree, we should keep it in a spiritual sense, just as we keep the Lord's Supper in a spiritual sense--but that doesn't mean that we forego keeping it physically as well. Every ritual in the Scripture is designed to let us "act out" something spiritual physically, so that full participation in God's blessings would not be limited to intellectuals and mystics, but be available to everyone.
The second question frequently asked is, "Don't you have to be circumcised to observe Passover?" Indeed you do (Exo. 12:48). However, the issue of circumcision is more than just a matter of a cutting of the flesh. By the 1st Century CE, it was an entire rabbinic ceremony by which a Gentile ceased to be a Greek, a Roman, etc., and became a full Jew, expected to keep all of the Torah and the Jewish traditions. It was believed that only the circumcised Jews could be saved (see Acts 15:1), basically excluding Gentiles from God's Kingdom. Now note that in Exodus 12:48, it does not say that the foreigner becomes a Jew when he is circumcised, nor does the ritual act make him a citizen of Israel. When the Apostles discouraged physical circumcision in favor of spiritual circumcision, they were dealing with a rabbinical tradition that committed the sin of adding to the Torah (cf. Deu. 12:32) and of Gentile exclusion.
It is wholly necessary for anyone celebrating God's deliverance of His people to be numbered among and fully identified with those people. However, in Col. 2:11, we are told that we are indeed circumcised spiritually ("without hands") when we trust in the Messiah, whether we are Jew ("circumcised" physically) or Gentile ("uncircumcised"). Therefore we are grafted in to Israel (Rom. 11), adopted into the family of Abraham (Rom. 4:11f, Gal. 3:29), whether or not we have been circumcised under the extra-Biblical ceremony that the non-believing Jewish rabbis and community would recognize.
Besides, if Sha'ul told the Corinthians, a mixed congregation (ch. 7-9) to keep the Passover, it must be appropriate for all believers to observe it. Any other decision would re-erect the wall of separation (Eph. 2:14) that Messiah came to break down.
And finally, the question arises whether it is appropriate to have lamb, when the Temple has been destroyed these last 2000 years (cf. Deu. 16:2). Many Messianic Jews do forgo lamb and substitute another meat in accordance with Jewish tradition and their own understanding about the requirement to have the lamb only in Jerusalem. That's fine, and it's possible that they are right. Now, it is correct that the proper Passover sacrifice, like all sacrifices (Deu. 12), must be offered only in Jerusalem at the Temple. However, as Christian commentators have so often observed, our proper sacrifice has already been offered in the proper place.
Therefore, to us, the Passover is no longer a proper sacrifice, but a memorial: "Do this in remembrance of Me" (Luke 22:19). Note that Yeshua does not repeat that formula for the wine, and yet every Christian considers it to include the wine in the Lord's Supper. Messianics understand it it include the whole of the Passover Seder as well, and at Beth HaMashiach, we believe it to include the lamb as well.
To those readers who have never experienced the joy of having the Passover Seder, I greatly encourage you to do so. It was one of the three life-changing events that led me to becoming Messianic, for truly, every single element speaks of our Lord.
Shalom!