What  are the normal parts of a Messianic liturgy? What should be included in the regular weekly Shabbat services? How can someone determine what should and should not be done? Are the regular Shabbats described in detail anywhere in the Bible?

More and more Messianic congregations are agreeing on the fact that there needs to be some sort of unification in their Messianic liturgy and worship celebrated in a Jewish manner. A common resource is the Messianic Siddur, which conveniently outlines the Shabbat services in Hebrew, tranliterated Hebrew and English.

Messianic Shabbat is held usually on Friday evenings (Erev Shabbat) or Saturday mornings, as God commanded the 7th day of the week to be the Sabbath. The celebration of Christmas and Easter are not encourage due to their pagan backgrounds, although often Messianics have Christian relatives. A cross is ususally not found in Messianic place of worship, but rather menorahs, Stars of David and and kippots are commonly seen. 

Almost universally,  Messianic celebrations include reading for the Torah scrolls, and many congregations observe the traditional Jewish annual calendar and reading assignments. Some are beginning to learn about and practice a more ancient three-year reading cycle that was typically used in the 1st century. Common songs of hallel that are sung may include: Shema, V’shamru, Amidah, Aleinu, Kaddish, Kiddush, Shehecheyanu, and Adon Olam.