What did Jesus mean by saying "only a few find the narrow gate"? Enter through the narrow gate. For wide is the gate and broad is the
  road that leads to destruction, and many enter through it. But small
  is the gate and narrow the road that leads to life, and only a few
  find it. (Matthew 7:13-14, NIV)


For any individual to enter the kingdom of God, it is necessary to use a gate. Why is it true that so few find this gate?
Matthew Chapter 7 is often thought to be in reference to those that will enter into the kingdom versus those that will not.  If one reads in advance to verse 13 they will discover that the opening line is “judge not, that ye be not judged” and what follows is a warning: “For with what judgment ye judge, ye shall be judged: and with what measure ye mete, it shall be measured to you again”.
Then in verses 7-11

“Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you…if ye then, being evil, know how to give good gifts unto your children, how much more shall your Father which is in heaven give good things to them that ask him?”  In verse 12 we are given insight: “Therefore all things whatsoever ye would that men should do to you, do ye even so to them: for this is the law and the prophets. Enter ye in at the strait gate: for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat: Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.”

This whole narrative is in regard to our relationship with one another.  “Judge not”,  “remove the plank out of your own eye”,  “whatsoever ye would that men should do to you”, this is the law of the Prophets.  In Matthew 22 Jesus also spoke of the law of the Prophets: “Love the Lord your God with all your heart and with all your soul and with all your mind… love your neighbor as yourself.”
Therefore in keeping with the narrative the wide gate that leads to destruction would be those works Paul speaks of that will not stand the test of fire and the narrow gate would be those works that stand the test of fire as they are conceived by God’s love.

1 Corinthians 3:8-…every man shall receive his own reward according to his own labour…Every man's work shall be made manifest: for the day shall declare it, because it shall be revealed by fire; and the fire shall try every man's work of what sort it is. If any man's work abide which he hath built thereupon, he shall receive a reward. If any man's work shall be burned, he shall suffer loss: but he himself shall be saved; yet so as by fire.

The word in Matthew 7 translated as “narrow” is done so only in this verse.  The Greek word being translated “thlibō” generally is translated as trouble or afflict.  Grace, Christ’s work on the cross (His trouble or affliction) is the narrow gate and the greatest love.  John 15:13 “Greater love hath no man than this, that a man lay down his life for his friends.”

John 10:9 &quot;I am the door (gate): by me if any man enter in, he shall be saved, and shall go in and out, and find pasture.&quot;
Matthew 16:24 &quot;Then said Jesus unto his disciples, If any man will come after me, let him deny himself, and take up his cross, and follow me&quot;