Heavenly Pilgrim said:
HP: What is it to have 'faith in vain?' I thought that it was faith alone and that if one has faith he is saved. This passage would appear to say that one can have faith, yet it is in vain in certain instances. That hangs 'faith alone' out to dry does it not? When is faith vain and when is it not? Is it vain from the start or just when one develops wrong ideas concerning the reserrection?
I don't think it's just faith, in this case it's faith in what. Anyone can go around and say I have faith but unless that faith is in the full Gospel of Jesus Christ then if I read Paul right, that faith is vain.
It is the Gospel, the complete Gospel that is the power of God unto salvation.
Ro 1:16 For I am not ashamed of the gospel of Christ:
for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek.
Also, I am not overlooking this part of your curiosity, "Is he addressing believers or non-believers?" I don't know how to answer it. As the others have said with the tare amongst the wheat, Mat 7 etc... I can't argue against that.
I had a preacher that sat under me a few years back that didn't believe Jesus was the Son of God. He'd argue with me and would bring in scripture(s) and stuff he downloaded from the internet. I never once questioned his salvation but I also never let him preach, teach etc...
Part of my understanding about the wheat and the tare is there is a good reason it isn't separated until harvest time...
Mt 13:24 Another parable put he forth unto them, saying, The kingdom of heaven is likened unto a man which sowed good seed in his field:
25 But while men slept, his enemy came and sowed tares among the wheat, and went his way.
26 But when the blade was sprung up, and brought forth fruit, then appeared the tares also.
27 So the servants of the householder came and said unto him, Sir, didst not thou sow good seed in thy field? from whence then hath it tares?
28 He said unto them, An enemy hath done this. The servants said unto him, Wilt thou then that we go and gather them up?
29 But he said,
Nay; lest while ye gather up the tares, ye root up also the wheat with them.
30
Let both grow together until the harvest: and in the time of harvest I will say to the reapers, Gather ye together first the tares, and bind them in bundles to burn them: but gather the wheat into my barn.
I don't think we are to know the difference;
Mt 13:41 The Son of man shall send forth his
angels, and
they shall gather out of his kingdom all things that offend, and them which do iniquity;
42 And shall cast them into a furnace of fire: there shall be wailing and gnashing of teeth.