Arcana Coelestia #23
23. Nothing is more common in the Word than for the word 'day' to be used to mean the particular time at which events take place, as in Isaiah,
The day of Jehovah is near. Behold, the day of Jehovah comes. I will make heaven tremble, and the earth will be shaken out of its place, on the day of My fierce anger. Its time is close at hand, and its days will not be prolonged. Isaiah 13:6, 9, 13, 22.
And in the same prophet,
Her antiquity is in the days of antiquity. On that day Tyre will be forgotten for seventy years, like the days of one king. Isaiah 23:7, 15.
Since 'day' stands for the particular time it also stands for the state associated with that particular time, as in Jeremiah, Woe to us, for the day has declined, for the shadows of evening have lengthened! Jeremiah 6:4
And in the same prophet,
If you break My covenant that is for the day and My covenant that is for the night, so that there is neither daytime nor night at their appointed time. Jeremiah 33:20, 25.
Also,
Renew our days as of old. Lamentations 5:21.
Arcana Coelestia #7882
7882. 'You shall keep it as a feast to Jehovah' means worship of the Lord because of deliverance from damnation. This is clear from the meaning of 'keeping a feast to Jehovah' as worship of the Lord, in particular because of deliverance from damnation, this being why that day is a feast day. The fact that the Passover was instituted because of the deliverance by the Lord of those who belonged to the spiritual Church, see 7867.