Revelation 13:18

 "And behold, I am coming quickly. 

Blessed is he who heeds the words of the prophecy of this book."     

Revelation 22:7  NASB

This calls for wisdom. Let the person who has insight calculate the number of the beast, for it is the number of a man. That number is 666.

This calls for wisdom 
Revelation 17:9  "This calls for a mind with wisdom. The seven heads are seven hills on which the woman sits."
Psalm 111:10  The fear of the LORD is the beginning of wisdom; all who follow his precepts have good understanding. To him belongs eternal praise.
Proverbs 2:6  For the LORD gives wisdom; from his mouth come knowledge and understanding.
Proverbs 3:13-14  Blessed are those who find wisdom, those who gain understanding, for she is more profitable than silver and yields better returns than gold.
Isaiah 11:2-3  The Spirit of the LORD will rest on him--the Spirit of wisdom and of understanding, the Spirit of counsel and of might, the Spirit of the knowledge and fear of the LORD--and he will delight in the fear of the LORD.
Jeremiah 10:12  But God made the earth by his power; he founded the world by his wisdom and stretched out the heavens by his understanding.
Colossians 2:2-3  My goal is that they may be encouraged in heart and united in love, so that they may have the full richness of complete understanding, in order that they may know the mystery of God, namely, Christ, in whom are hidden all the treasures of wisdom and knowledge.
James 1:5  If any of you lacks wisdom, you should ask God, who gives generously to all without finding fault, and it will be given to you.

for it is the number of a man 
Revelation 13:16-17  It also forced all people, great and small, rich and poor, free and slave, to receive a mark on their right hands or on their foreheads, so that they could not buy or sell unless they had the mark, which is the name of the beast or the number if its name. 
Revelation 15:2  And I saw what looked like a sea of glass glowing with fire and, standing beside the sea, those who had been victorious over the beast and its image and over the number of its name. They held harps given them by God ...

Scriptures taken from the Holy Bible, New International Version® NIV®, Copyright© 1973, 1978, 1984, 2011 by Biblica, Inc.® Used by permission. All rights reserved worldwide. 
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