In Christianity, Holy Tuesday is the last Tuesday prior to Easter Sunday; it is the third day of Holy Week after Palm Sunday and Holy Monday. Depending on the denomination, this day may or may not be celebrated at all. Those that do observe Holy Tuesday, such as Eastern Orthodox churches, typically mark it with readings of particular passages of Scriptures and the singing of relevant hymns.
According to common interpretation of the Bible, Holy Tuesday is when Jesus was issued various challenges by the Pharisees and Sadducees over subjects such as marriage in heaven, paying taxes to Caesar, and the source of His authority (Matthew 21:23—23:39; Mark 11:27—12:44; Luke 20:1—21:4). By this same interpretation, this is the day Jesus commented on the widow’s donation (Mark 12; Luke 21) and was approached by a number of God-fearing Greeks (John 12:20–36). Tuesday would also be the day Jesus spoke His eight “woes” against the Pharisees (Matthew 23:13–36) and the evening on which He delivered the Olivet Discourse (Matthew 24—25; Mark 13; Luke 21:5–36).
Holy Tuesday is the day following Holy Monday, and the next day in Holy Week is sometimes referred to as Holy Wednesday or Spy Wednesday.
It should be noted that events in the Gospels were not necessarily recorded chronologically. Also, Roman and Jewish days started at different times, making the chronology even more difficult to sort out. For these reasons, it’s unwise to be dogmatic about precisely which events occurred on which days leading up to Jesus’ arrest and crucifixion.