Four

Four is not a particularly special number. There is a sequence in Proverbs 30, of "three, yes 4", which have four points each (verses 15, 18, 21, 24, and 29). There is often a punctuating statement at the end ("The eye [that] mocketh at [his] father, and despiseth to obey [his] mother, the ravens of the valley shall pick it out, and the young eagles shall eat it." - verse 17 after the verse 15-16 list).

In Amos, there are several "three and four" statements. But these have seven parts. Pastor Wilson did an excellent exposition on them.

Finally, John describes four living creatures before God's throne (Revelation 4:6). They are:

• Lion - king of the wild animals
• Calf - probably representative of the ox (the Greek is "young bull"), strongest of the tame animals
• Man
  
• Eagle - highest flying of the birds

These beings seem to represent all of creation worshiping God.