The number "four" in the Bible represents things being linked together or joined. This is partly because four is two times two, and two represents the ultimate linking between our desire to be good and our understanding of truth. We can also see this in the fact that most buildings are rectangular, with the four sides linking together to make a whole. We also divide directions into four -- north, east, south and west -- and talk about the "four corners" of something meaning all of it. So our special thinking naturally looks at four sides as linking together into a whole.

(References: Apocalypse Explained 417; Arcana Coelestia 1686, 9103, 9601, 9767, 9864)

In Genesis 19:37; 21:26; 30:32; 40:7; Matthew 6:30; Luke 12:28, this signifies the perpetuity and eternity of a state. (Arcana Coelestia 2838)

In Psalm 2:7, this signifies in time; for with Jehovah the future is present. (True Christian Religion 101)

The expression 'even to this day' or 'today' sometimes appears in the Word, as in Genesis 19:37-38, 22:14, 26:33, 32:32, 35:20, and 47:26. In a historical sense, these expressions have respect to the time when Moses lived, but in an internal sense, 'this day' and 'today' signify the perpetuity and eternity of a state. 'Day' denotes state, and likewise 'today,' which is the current time. Anything related to time in the world is eternal in heaven, and to represent this, 'today' or 'to this day' is added. Although, in the historical sense, this appears as if the expressions only have a literal meaning, just like it says in other parts of the Word, such as Joshua 4:9, 6:25, 7:20, Judges 1:21, 26, etc. 'Today' means something perpetual and eternal in Psalms 2:7, 119:89-91, Jeremiah 1:5, 10, 18, Deuteronomy 29:9-14, Numbers 28:3, 23, Daniel 8:13, 11:31, 12:11, Exodus 16:4, 19, 20, 23, John 6:31, 32, 49, 50, 58, Matthew 6:11, and Luke 11:3.

(References: Arcana Coelestia 2838 [1-4], Genesis 47:26)