The best way of understanding the passage in which the expression "narrow gate" is found is to do an exegesis of it by answering the following questions:
Here are my suggested answers as requested by my Aussie cobber:
The general crowds, including His disciples, common people, and religious leaders.
What is His intention for saying these things?
To show them God's standards for holy living.
How would His First Century Jewish listeners understand what He is teaching them?
They would understand that following just the external rules of the Law, but the obedience needs to go deeper, into their hearts.
What kind of judgments is Jesus saying they should not make?
Personal judgments of people. This doesn't include appropriate judgment of doctrines, Bible teachings, church practices, claims of signs, wonders, and healing. For example, the golden shower in a Bethel church. Two women members confessed that their job was to put ground up glitter into the ventilation system to make it appear that God was scattering gold dust from heaven on to the congregation. I can judge that act as deliberate deception of unwary people and it would make me doubt the showering of feathers as well. Therefore I can further judge that the leaders who set that up are wolves and false teachers and deceivers. But I can't judge the personal life of any of those people or leaders, because we are all just poor sinners and nothing at all. But when it comes to discerning falsehood in teaching and claims, then we should make judgments based on God's Word. (whoops! I was using hermeneutics here!)
What is His definition of a hypocrite in that context?
The person who tries to take a speck out of his brother's eye when he has a great log in his own. It is like two filthy, lice infested beggars sitting in a ditch and one saying to another, "You stink!"
What are the dogs, and why would they not encouraged to give them that which is holy?
The dogs in the First Century were not the lovable pets we have today. These were wild dogs who would bit the hand of anyone who tried to feed them. If they were fed, they would just wolf it all down and bite you anyway. They are the same as the swine which would trample down any pearls you would give them. So those things that are sacred and holy to them should not be given to those who would not appreciate them but would just throw them back into their faces.
Why did Jesus tell people to ask, seek and knock?
Because that is how to get God's door opened to them to receive the promises.
How can His listeners be assured that God would give them good gifts?
Because if evil and godless people know how to give good gifts to their children and God is so much better than that.
What is the Law and the Prophets in this context?
Do to others as you would have them do unto you.
Where does the wide gate lead to?
To destruction - in other words, an eternity in hell.
Where does the narrow gate lead to?
Eternal life in Christ.
He is a wolf in sheep's clothing. Someone who appears to be good and holy, but has evil intentions.
How would His listeners recognise them?
By their fruits - the outcomes in the lives of those who follow their prophecies.
Why did Jesus say that not everyone who said Lord, Lord, will be rejected? (explain it in the context as understood by the First Century listeners, not how you would understand it today).
Because they did not do what He told them to do. they may have done some wonderful and great things, but Jesus did not tell them to do them.
How would Jesus recognise workers of lawlessness (from the context)?
Those who fail to do the will of God.
Why would the man who built his house upon the rock be wise?
Because he heard the words of Jesus and did them.
So this is my fairly simple exegesis of the passage in its original context. I have tried to resist the temptation to do hermeneutics and comment on how we should apply them today (although I did fail a couple of times. Couldn't help it!)
Now, my good brother from across the ditch, what are your comments?
Then we'd all know.
