Matthew 7:21-23, Matthew 25:1-13, ​Luke 6:46-49, and ​Luke 13:24-28

​​These four passages are clearly connected (all have people saying "Lord, Lord"), and their parallels are worth examining.
​Matthew 7:21-23
  • Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven. Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? And then will I profess unto them, I never knew you: depart from me, ye that work iniquity. (Matthew 7:21-23)
Many teachers profess that this is clear evidence that people can lose their salvation, or that we have to work to go to heaven.  One of the ironies is that the same passage shows that those who won't enter heaven were people who were offering their own achievements to Jesus, saying they had done many wonderful works.  This is also a verse that's often edited in new Bible versions to subtly disguise this truth, but that's another topic.

Something else that's often overlooked by these teachers is that He says He never knew them.  Not that He knew them once and then forgot them, or something like that.  If He never knew them then they were never saved.  I believe this group of people are those who have trusted in their works to some degree to be saved.  They believed they were saved, but they had believed a false gospel that included their own efforts.

​Scripture makes it clear that Jesus Christ knows those who are saved:
  • ¶ Nevertheless the foundation of God standeth sure, having this seal, The Lord knoweth them that are his. And, Let every one that nameth the name of Christ depart from iniquity. (2 Timothy 2:19) 
  • ¶ And be found in him, not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith: That I may know him, and the power of his resurrection, and the fellowship of his sufferings, being made conformable unto his death; (Philippians 3:9-10)
  • And we know that the Son of God is come, and hath given us an understanding, that we may know him that is true, and we are in him that is true, [even] in his Son Jesus Christ. This is the true God, and eternal life. (1 John 5:20)
  • And because ye are sons, God hath sent forth the Spirit of his Son into your hearts, crying, Abba, Father. Wherefore thou art no more a servant, but a son; and if a son, then an heir of God through Christ. ¶ Howbeit then, when ye knew not God, ye did service unto them which by nature are no gods. But now, after that ye have known God, or rather are known of God, how turn ye again to the weak and beggarly elements, whereunto ye desire again to be in bondage? (Galatians 4:6-9)
  • I am the good shepherd, and know my [sheep], and am known of mine. (John 10:14)
  • My sheep hear my voice, and I know them, and they follow me: And I give unto them eternal life; and they shall never perish, neither shall any [man] pluck them out of my hand. My Father, which gave [them] me, is greater than all; and no [man] is able to pluck [them] out of my Father's hand. (John 10:27-29)
  • But ye believe not, because ye are not of my sheep, as I said unto you. (John 10:26) 
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Another important point is that He mentions whoever does the will of the Father will enter the kingdom of heaven.  But what's the will of the Father?
  • And this is the Father's will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day. And this is the will of him that sent me, that ​every one which seeth the Son, and believeth on him, may have everlasting life: and I will raise him up at the last day. (John 6:39-40) 
So, it's believing on Jesus Christ that's the Father's will.  It's believing the simple gospel.  Then those who are saved will enter the kingdom of heaven, and won't be outside knocking and proclaiming their wonderful works.


​Matthew 25:1-13
  • Then shall the kingdom of heaven be likened unto ten virgins, which took their lamps, and went forth to meet the bridegroom. And five of them were wise, and five [were] foolish. They that [were] foolish took their lamps, and took no oil with them: But the wise took oil in their vessels with their lamps. While the bridegroom tarried, they all slumbered and slept. And at midnight there was a cry made, Behold, the bridegroom cometh; go ye out to meet him. Then all those virgins arose, and trimmed their lamps. And the foolish said unto the wise, Give us of your oil; for our lamps are gone out. But the wise answered, saying, [Not so]; lest there be not enough for us and you: but go ye rather to them that sell, and buy for yourselves. And while they went to buy, the bridegroom came; and they that were ready went in with him to the marriage: and the door was shut. Afterward came also the other virgins, saying, Lord, Lord, open to us. But he answered and said, Verily I say unto you, I know you not. Watch therefore, for ye know neither the day nor the hour wherein the Son of man cometh. (Matthew 25:1-13)

Before taking a look at this, it bears repeating that Jesus seemed to say that parables were meant to be misinterpreted by the carnal mind:
  • Therefore speak I to them in parables: because they seeing see not; and hearing they hear not, neither do they understand. And in them is fulfilled the prophecy of Esaias, which saith, By hearing ye shall hear, and shall not understand; and seeing ye shall see, and shall not perceive: For this people's heart is waxed gross, and [their] ears are dull of hearing, and their eyes they have closed; lest at any time they should see with [their] eyes, and hear with [their] ears, and should understand with [their] heart, and should be converted, and I should heal them. (Matthew 13:13-15)

Throughout the scriptures, oil is used as a metaphor for the Holy Spirit.  Oil is used for anointing, and the Holy Spirit seals us when we're saved.  There's a clear similarity.
  • And thou shalt make it an oil of holy ointment, an ointment compound after the art of the apothecary: it shall be an holy anointing oil. (Exodus 30:25)
  • And he poured of the anointing oil upon Aaron's head, and anointed him, to sanctify him. (Leviticus 8:12)
  • Then Samuel took the horn of oil, and anointed him in the midst of his brethren: and the Spirit of the LORD came upon David from that day forward. So Samuel rose up, and went to Ramah. (1 Samuel 16:13) 
  • ¶ The Spirit of the Lord GOD [is] upon me; because the LORD hath anointed me to preach good tidings unto the meek; he hath sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to [them that are] bound; (Isaiah 61:1) 
  • ​The Spirit of the Lord [is] upon me, because he hath anointed me to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised, (Luke 4:18)
  • How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing all that were oppressed of the devil; for God was with him. (Acts 10:38)
  • In whom ye also [trusted], after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise, Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory. (Ephesians 1:13-14)
So the wise virgins were saved, as they had oil in their lamps.  The unwise virgins were unsaved; they were without oil.  Further evidence that this is about the difference between the saved and unsaved, between those who believed the true gospel versus those who believed another gospel (i.e. that they had to work to be saved, to some degree), is that the unwise virgins attempted to purchase oil.  I believe it's obvious that they were attempting to purchase their salvation with their works.

Here is another parable that's talking about the same thing--being ready (I think that can mean getting saved in time, among other things, as I also don't think any of us would want to first meet our Savior in a bad condition) and having our lights burning:
  • Let your loins be girded about, and [your] lights burning; And ye yourselves like unto men that wait for their lord, when he will return from the wedding; that when he cometh and knocketh, they may open unto him immediately. Blessed [are] those servants, whom the lord when he cometh shall find watching: verily I say unto you, that he shall gird himself, and make them to sit down to meat, and will come forth and serve them. (Luke 12:35-37)
And notice the reference to unbelievers.  Also take note how He's talking about what seems to be the will of the Father again (which we understand is to get saved):
  • The lord of that servant will come in a day when he looketh not for [him], and at an hour when he is not aware, and will cut him in sunder, and will appoint him his portion with the unbelievers. And that servant, which knew his lord's will, and prepared not [himself], neither did according to his will, shall be beaten with many [stripes]. (Luke 12:46-47)

Sidenote: often this passage is also included in the Lordship Salvationist teaching about the ten virgins:
  • ​Husbands, love your wives, even as Christ also loved the church, and gave himself for it; That he might sanctify and cleanse it with the washing of water by the word, That he might present it to himself a glorious church, not having spot, or wrinkle, or any such thing; but that it should be holy and without blemish. (Ephesians 5:25-27)
But our spirits are perfectly sanctified after we're saved, so when we're freed of our flesh at His coming (when our physical bodies die) we will no longer sin and will be perfect for Him.

And one final argument I can make in favor of this parable not supporting salvific loss is an analysis of the groups being discussed.  Looking at this parable the whole group considered is ten virgins:
  • ¶ Then shall the kingdom of heaven be likened unto ten virgins, which took their lamps, and went forth to meet the bridegroom. And five of them were wise, and five [were] foolish. (Matthew 25:1-2)

A parallel passage for the kingdom of heaven can be found here, where we can see the kingdom of heaven, or the whole group, portrayed as including unsaved and saved (and everyone, not just people who were saints, every kind), and that's the distinction:
  • Again, the kingdom of heaven is like unto a net, that was cast into the sea, and gathered of every kind: Which, when it was full, they drew to shore, and sat down, and gathered the good into vessels, but cast the bad away. So shall it be at the end of the world: the angels shall come forth, and sever the wicked from among the just, And shall cast them into the furnace of fire: there shall be wailing and gnashing of teeth. (Matthew 13:47-50)

Who are the just?
  • But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness. (Romans 4:5)
  • Knowing that a man is not justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be justified by the faith of Christ, and not by the works of the law: for by the works of the law shall no flesh be justified. (Galatians 2:16)

And to reinforce and add to the point, the kingdom of heaven's (or as we can see, the world's) good seed definitely grows into wheat in this parable, unless one thinks that good seed would produce tares.
¶ Another parable put he forth unto them, saying, The kingdom of heaven is likened unto a man which sowed good seed in his field: But while men slept, his enemy came and sowed tares among the wheat, and went his way. (Matthew 13:24-25)
The field is the world; the good seed are the children of the kingdom; but the tares are the children of the wicked [one]; (Matthew 13:38)
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. (Matthew 13:30)

So to equate the foolish virgins to saints who lost their salvation is to miss the greater context of these parallel parables, as well as word usage and other scriptures which support the doctrine of Once Saved Always Saved.

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Luke 6:46-49
  • And why call ye me, Lord, Lord, and do not the things which I say? Whosoever cometh to me, and heareth my sayings, and doeth them, I will shew you to whom he is like: He is like a man which built an house, and digged deep, and laid the foundation on a rock: and when the flood arose, the stream beat vehemently upon that house, and could not shake it: for it was founded upon a rock. But he that heareth, and doeth not, is like a man that without a foundation built an house upon the earth; against which the stream did beat vehemently, and immediately it fell; and the ruin of that house was great. (Luke 6:46-49) 
Clearly this is a reference to the same thing in the other examples.  And what are some of Jesus' sayings that we can do?  We can believe, as He commands:
  • And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel. (Mark 1:15)
  • But if I do, though ye believe not me, believe the works: that ye may know, and believe, that the Father [is] in me, and I in him. (John 10:38)
  • While ye have light, believe in the light, that ye may be the children of light. These things spake Jesus, and departed, and did hide himself from them. (John 12:36)
  • Believe me that I [am] in the Father, and the Father in me: or else believe me for the very works' sake. (John 14:11)


Luke 13:24-28
  • Strive to enter in at the strait gate: for many, I say unto you, will seek to enter in, and shall not be able. When once the master of the house is risen up, and hath shut to the door, and ye begin to stand without, and to knock at the door, saying, Lord, Lord, open unto us; and he shall answer and say unto you, I know you not whence ye are: Then shall ye begin to say, We have eaten and drunk in thy presence, and thou hast taught in our streets. But he shall say, I tell you, I know you not whence ye are; depart from me, all [ye] workers of iniquity. There shall be weeping and gnashing of teeth, when ye shall see Abraham, and Isaac, and Jacob, and all the prophets, in the kingdom of God, and you [yourselves] thrust out. (Luke 13:24-28)
We see again the same theme of people who are trusting in their works.  They ate and drank in His presence, and taught in the streets.  But that did not mean He knew them.  And, in the next passage, we see that this subject of who enters the kingdom of heaven is about faith, and that the children of the kingdom, or the corporate unbelieving kingdom of Israel (not all of them), will be cast into outer darkness.
  •  When Jesus heard [it], he marvelled, and said to them that followed, Verily I say unto you, I have not found so great faith, no, not in Israel. And I say unto you, That many shall come from the east and west, and shall sit down with Abraham, and Isaac, and Jacob, in the kingdom of heaven. But the children of the kingdom shall be cast out into outer darkness: there shall be weeping and gnashing of teeth. (Matthew 8:10-12) 
I don't agree with everything that Steven Anderson says, but I think this is a great video on the topic.