The phrase "since birth of Jesus Christ" refers to events, beliefs, and traditions originating from the time of Jesus' birth. Some synonyms for this phrase include "since the advent of Jesus," "since the Nativity of Christ," and "since the birth of the Savior." These phrases are often used to describe the establishment of Christian faith and the impact of Jesus' teachings on the world. Other synonyms that relate to this concept include "Christian era," "after Christ," and "Anno Domini," which translates to "in the year of the Lord" in Latin. All of these terms serve to point to the central importance of Jesus' birth in shaping human history.