A.T. Robertson 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)

Which departed not (η ουκ αφιστατο). Imperfect indicative middle. She kept on not leaving. The Spirit kept her in the temple as he led Simon to the temple (Plummer). The case of "the temple" (του ιερου) is ablative.

Night and day (νυκτα κα ημεραν). Accusative of duration of time, all night and all day. She never missed a service in the temple.