Today is sometimes called The Feast of the Purification of the Virgin Mary and sometimes The Presentation of Our Lord Jesus Christ:
Here's part of what James Kiefer said:
Counting forward from December 25 as Day One, we find that Day Forty is February 2. A Jewish woman is in semi-seclusion for 40 days after giving birth to a son, and accordingly it is on February 2 that we celebrate the coming of Mary and Joseph with the infant Jesus to the Temple at Jerusalem...The old Celtic name for this day is Imbolc or Oimelk which are a references to the pregnancy and lactating of the ewes. It is considered the first day of spring.
Because an old reading for this festival contains the line (Zephaniah 1:12), "I will search Jerusalem with candles," the day is also known as Candlemas, and sometimes observed with a candle-lit procession.