Albert Barnes Commentary Luke 2:37

"and she had been a widow even unto fourscore and four years), who departed not from the temple, worshipping with fastings and supplications night and day." — Luke 2:37 (ASV)

And she was a widow of about four-score and four years. That is, she was about eighty-four years of age. It does not mean that she had been a widow for that long time.

"Fastings and prayers." This refers to constant religious service. This involved spending her time in prayer and in all the ordinances of religion.

"Night and day." This means continually—that is, at the usual times of public worship and in private. When it is said that she departed not from the temple, it is meant that she was constant and regular in all the public services at the temple, or was never absent from those services. God blesses those who wait at his temple gates.