Answer
Throughout the Bible, God often gives symbolic significance to mundane items or concepts. For example, in Genesis 9:12–16, God makes the rainbow the sign of His promise to Noah (and, by extension, to all mankind) that He will not flood the whole earth again. God uses bread as a representation of His presence with His people (Numbers 4:7); of the gift of eternal life (John 6:35); and of the broken body of Christ, sacrificed for our sins (Matthew 26:26). The rainbow and the bread are obvious symbols in Scripture. Less obvious meanings seem to be attached to some numbers in the Bible, especially the number 7, which at times provides a special emphasis in the text.
The first use of the number 7 in the Bible relates to the creation week in Genesis 1. God spends six days creating the heavens and the earth, and then rests on the seventh day. This is our template for the seven-day week, observed around the world to this day. The seventh day was to be “set apart” for Israel; the Sabbath was a holy day of rest (Deuteronomy 5:12).
Thus, right at the start of the Bible, the number 7 is identified with something being “finished” or “complete.” From then on, that association continues, as 7 is often found in contexts involving completeness or divine perfection. So we see the command for animals to be at least seven days old before being used for sacrifice (Exodus 22:30), the command for leprous Naaman to bathe in the Jordan River seven times to effect complete cleansing (2 Kings 5:10), and the command for Joshua to march around Jericho for seven days (and on the seventh day to make seven circuits) and for seven priests to blow seven trumpets outside the city walls (Joshua 6:3–4). In these instances, 7 signifies a completion of some kind: a divine mandate is fulfilled.
Interestingly, man was created on the sixth day of creation. In some passages of the Bible, the number 6 is associated with mankind. In Revelation “the number of the beast” is called “the number of a man.” That number is 666 (Revelation 13:18). If God’s number is 7, then man’s is 6. Six always falls short of seven, just like “all have sinned and fall short of the glory of God” (Romans 3:23). Man is not God, just as 6 is not 7.
Series of seven things crop up often in the Bible. For example, we find seven pairs of each clean animal on the ark (Genesis 7:2); seven stems on the tabernacle’s lampstand (Exodus 25:37); seven qualities of the Messiah in Isaiah 11:2; seven signs in John’s Gospel; seven things the Lord hates in Proverbs 6:16; seven parables in Matthew 13; and seven woes in Matthew 23.
Multiples of 7 also figure into the biblical narrative: the “seventy weeks” prophecy in Daniel 9:24 concerns 490 years (7 times 7 times 10). Jeremiah 29:10 predicted the Babylonian Captivity would last for seventy years (7 times 10). According to Leviticus 25:8, the Year of Jubilee was to begin after the passing of every forty-ninth year (7 times 7).
Sometimes, the symbolism of 7 is a great comfort to us: Jesus is the seven-fold “I AM” in the Gospel of John. Other times, it challenges us: Jesus told Peter to forgive a wrongdoer “seventy times seven” times (Matthew 18:22, NKJV). And then there are passages in which the number 7 is associated with God’s judgment: the seven bowls of the Great Tribulation, for example (Revelation 16:1), or God’s warning to Israel in Leviticus 26:18.
Speaking of the book of Revelation, the number 7 is used there more than fifty times in a variety of contexts: there are seven letters to seven churches in Asia and seven spirits before God’s throne (Revelation 1:4), seven golden lampstands (Revelation 1:12), seven stars in Christ’s right hand (Revelation 1:16), seven seals of God’s judgment (Revelation 5:1), seven angels with seven trumpets (Revelation 8:2), etc. In all likelihood, the number 7 again represents completeness or totality: the seven churches represent the completeness of the body of Christ, the seven seals on the scroll represent the fullness of God’s punishment of a sinful earth, and so on. And, of course, the book of Revelation itself, with all its 7’s, is the capstone of God’s Word to man. With the book of Revelation, the Word was complete (Revelation 22:18).
Of course, not every instance of the number 7 in the Bible carries a deeper significance. Sometimes, a 7 is just a 7, and we must be cautious about attaching symbolic meanings to any text, especially when Scripture is not explicit about such meanings. However, there are times when it seems that God is communicating the idea of divine completeness, perfection, and wholeness by means of the number 7.