From John Bunyan's classic The Pilgrim's Progress, Part I, Section 5, Step 4.
Now, after awhile, they perceived afar off, one coming softly, and alone, all along the highway, to meet them. Then said Christian to his fellow, Yonder is a man with his back towards Zion, and he is coming to meet us.
Hopeful: I see him; let us take heed to ourselves now, lest he should prove a Flatterer also. So he drew nearer and nearer, and at last came up to them. His name was Atheist, and he asked them whither they were going.
Christian: We are going to Mount Zion.
Then Atheist fell into a very great laughter.
Christian: What's the meaning of your laughter?
Atheist: I laugh to see what ignorant persons you are, to take upon you so tedious a journey, and yet are like to have nothing but your travel for your pains.
Christian: Why, man, do you think we shall not be received?
Atheist: Received! There is not such a place as you dream of in all this world.
Christian: But there is in the world to come.
Atheist: When I was at home in mine own country I heard as you now affirm, and from that hearing went out to see, and have been seeking this city these twenty years, but find no more of it than I did the first day I set out (Eccles. 10:15; Jer. 17:15).
Christian: We have both heard, and believe, that there is such a place to be found.
Atheist: Had not I, when at home, believed, I had not come thus far to seek; but finding none, (and yet I should, had there been such a place to be found, for I have gone to seek it farther than you,) I am going back again, and will seek to refresh myself with the things that I then cast away for hopes of that which I now see is not.
Christian: Then said Christian to Hopeful his companion, Is it true which this man hath said?
Hopeful: Take heed, he is one of the Flatterers. Remember what it cost us once already for our hearkening to such kind of fellows. What! no Mount Zion? Did we not see from the Delectable Mountains the gate of the city? Also, are we not now to walk by faith? (2 Cor. 5:7) Let us go on, lest the man with the whip overtake us again. You should have taught me that lesson, which I will sound you in the ears withal: "Cease, my son, to hear the instruction that causeth to err from the words of knowledge" (Prov. 19:27). I say, my brother, cease to hear him, and let us believe to the saving of the soul.
Christian: My brother, I did not put the question to thee, for that I doubted of the truth of our belief myself, but to prove thee, and to fetch from thee a fruit of the honesty of thy heart. As for this man, I know that he is blinded by the God of this world. Let thee and me go on, knowing that we have belief of the truth; and no lie is of the truth (1 John 5:21).
Hopeful: Now do I rejoice in hope of the glory of God. So they turned away from the man; and he, laughing at them, went his way.