Today is the feast of the Presentation of the Blessed Virgin Mary or, as it is known in the East, The Entry of the Most Holy Theotokos [God-Bearer] into the Temple.
The earliest attestation of this tradition is in the Proto-Gospel of James (Protevangelium Jacobi):
When the child turned three, Joachim said, ‘Let us call the undefiled daughters of the Hebrews. Let each of them take a lamp, and let each stand burning so that the child might not turn back and her heart be captivated by things outside the temple of the Lord.’ This is what they did until they came up to the temple of the Lord. And the priest welcomed her, kissed her, blessed her, and said, ‘The Lord God has magnified your name among all generations. In you the Lord will manifest his redemption to the sons of Israel in the last days.’ He placed her on the third step of the altar, and God showered her with grace. She danced with her feet, and the entire house of Israel loved her (PJ 7:4-10).
From the Festal Menaion:
Having received the fruit of the promise come from the Lord, today in the temple Joachim and Ann offered the Mother of God as an acceptable sacrifice; and Zacharias the great High Priest received her with his blessing.
Into the holy places the Holy of Holies is fittingly brought to dwell, as a sacrifice acceptable to God. The virgins adorned by virtues go before her carrying torches, and offer her to God as a most sacred Vessel.
Let the gate of the temple wherein God dwells be opened: for Joachim brings within today in glory the Temple and Throne of the King of all, and he consecrates as an offering to God her whom the Lord has chosen to be his Mother.
*the image at the start of this post is a fresco from the Scrovegni (Arena) Chapel in Padua, painted by Giotto.