Great Lent and Holy Week are two separate fasts, and two separate celebrations. Great Lent ends on Friday of the fifth week (the day before Lazarus Saturday). Holy Week begins immediately thereafter. Let's explore the meaning of each of the solemn days of Passion Week.
Lazarus Saturday: Lazarus Saturday is the day which begins Holy Week. It commemorates the raising of our Lord's friend Lazarus, who had been in the tomb four days. This act confirmed the universal resurrection from the dead that all of us will experience at our Lord's Second Coming. This miracle led many to faith, but it also led to the chief priest's and Pharisees' decision to kill Jesus (John 11:47-57).
Palm Sunday (The Entrance of our Lord into Jerusalem): Our Lord enters Jerusalem and is proclaimed king - but in an earthly sense, as many people of His time were seeking a political Messiah. Our Lord is King, of course, but of a different type - the eternal King prophesied by Zechariah the Prophet. We use palms on this day to show that we too accept Jesus as the true King and Messiah of the Jews, Who we are willing to follow - even to the cross.
Holy Monday, Tuesday and Wednesday: The first thing that must be said about these services, and most of the other services of Holy Week, is that they are "sung" in anticipation. Each service is rotated ahead twelve hours. The evening service, therefore, is actually the service of the next morning, while the morning services of Holy Thursday and Holy Saturday are actually the services of the coming evening.
Understanding that, let's turn to the Services of Holy Monday, Tuesday and Wednesday (celebrated Palm Sunday , Monday and Tuesday evening). The services of these days are known as the Bridegroom or Nymphios Orthros Services. At the first service of Palm Sunday evening, the priest carries the icon of Christ the Bridegroom in procession, and we sing the "Hymn of the Bridegroom." We behold Christ as the Bridegroom of the Church, bearing the marks of His suffering, yet preparing a marriage Feast for us in God's Kingdom.