Hello 2Christ, I agree
Assurance can be a fleeting thing to be sure (and we should not "assume" anything, of course), but I believe that the Lord wants us to be certain of our salvation/that we are truly "in Christ", and that during our walk before/with Him ~in this life~! He commands us to so do more than once, and He also tells us plainly that we can and should be sure (that we have been saved & that we ~already~ possess "eternal life", and that from the very moment that we first believe .. e.g. John 5:24).
For instance,
2 Corinthians 13
5 Test yourselves ~to see if you are in the faith~; examine yourselves! Or do you not recognize this about yourselves, that Jesus Christ is in you—unless indeed you fail the test?
1 John 5
13 These things I have written to you who believe in the name of the Son of God, so that you may ~know~ that you have ~eternal life~.
Actually, I believe that "those who endure to the end" is a description of true believers, not an admonishment or command for us to do so .. e.g. Matthew 10:22, Matthew 24:13, Mark 13:13.
Yes, He is telling us that there are many who "claim" (and may even believe) that they are Christians in the church, but also that what they "do" reveals who they really "are" (a bad tree cannot produce good fruit, even if it appears to be "good" at first blush).
Agreed. Of course, I wonder if some (or most) of those who will be standing in that Judgment (GWT) will truly be expecting to be judged worthy of living out eternity with Him, or if they are simply lying about what they did in this life instead? I mean, considering the alternative that will be set before them and the precipice upon which they will be standing at that particular moment in time (the Lake of Fire), can you blame them 
Here we disagree, because I believe that the key to everything that is being said in this short passage is found in the four words above in bold, "I NEVER knew you". That's why their deeds (whether miraculous or mundane) were "lawless", because those who do not know the Lord cannot do anything in accord with His Divine will, nor by His power. Our "knowing Him" and His "knowing us" is the key, the personal relationship, that is, from which everything in the Christian life flows (as He also told us in His high, priestly prayer),
John 10
3 ~THIS~ is eternal life, that they may ~know~ You, the only true God, and Jesus Christ whom You have sent.
So, whatever we do as Christians (in Christ) is wholly dependent upon our knowing Him, and He us, and on the growing "personal" relationship that we have, with Him (the One who saved us, and who also promised to sanctify us and keep us safe, from here to Glory .. e.g. John 10:27-28; Philippians 1:6; 1 Thessalonians 5:23-24; Hebrews 7:25, Jude 24-25).
Here again I disagree, and that for the same reason, because the most important context here is about who we are, not about what we do (because what we do results from who we are, or more specifically, of who we have become, by Him and in Him).
That said, the latter (obedience, good deeds, holy living, etc.) is certainly important, because it is the evidence that shows us who we really are, true Christian or CINO (or as @mailmandan says, "believers" or "make believers" 
).
Agreed, of course.
I'd like to be clear about something at this point. I hold to "Lordship Salvation", by which I mean that a true believer is not ~required~ to do good deeds, but that he/she ~will~ do good deeds (among the many other things that accompany our salvation), not to become or remain "saved", but because we already ~are~ saved .. e.g. Ephesians 2:4-5, Ephesians 2:8-10; Titus 3:5.
What I am ~not~ is a believer in "works righteousness", in any sense of what that means. There is no 'initial' salvation, for instance, that begins as something that is wholly gracious, but is then morphed somehow into a salvation that is based, even in part, on what 'we' do instead, because again, what we do is a matter of who we are/who we have become, so it's only what He did 'for us' that truly matters (or "counts" toward our redemption, forgiveness & salvation).
AGREED 
In fact, if that's what you believe, specifically (the words above in bold, that is) then it seems that we are on the same page about most or all of this 
Well, I agree that we will not "hear" the final verdict from Him directly until after we die, but that hardly means that we cannot know, or that He does not expect us to know, what His verdict will be in the here and now (e.g. 1 John 5:13).
God bless you!!
~Deuteronomy
Good Morning Deuteronomy,
I agree that knowing Christ is essential. No Christian would deny that. But I don't think Jesus separates knowing Him from obeying Him. Throughout His teaching, He joins the two together.
Jesus said,
"If ye love me, ye will keep my commandments." (John 14:15, ASV)
He also said,
"He that hath my commandments, and keepeth them, he it is that loveth me." (John 14:21, ASV)
And again,
"If ye keep my commandments, ye shall abide in my love; even as I have kept my Father's commandments, and abide in his love." (John 15:10, ASV)
So the question is not whether a relationship with Christ is important. It certainly is. The question is how Jesus says that relationship is shown and continued. His answer is obedience.
Matthew 7 itself makes this clear. Jesus does not simply say, "I never knew you." He also gives the reason for His judgment:
"Depart from me, ye that work iniquity." (Matthew 7:23, ASV). If "I never knew you" were the whole explanation, there would have been no need to add that they were workers of lawlessness. Jesus deliberately includes both. They claimed to serve Him, but their lives were marked by disobedience.
The surrounding context points to the same conclusion. First, Jesus warns that false prophets are known by their fruits (Matthew 7:15-20). Then He says that not everyone who calls Him "Lord" will enter the kingdom, but only those who do the will of His Father (Matthew 7:21). Finally, He compares the wise man with the foolish man. The difference is not that one heard His words and the other did not. Both heard. The difference is that one obeyed while the other did not (Matthew 7:24-27). The entire passage is about obedience flowing from genuine faith.
I also don't think Scripture supports the idea that someone who once truly served God could never later fall away.
Judas is an obvious example. Jesus chose him as one of the Twelve and sent him out with the others to preach repentance, heal the sick, and cast out demons (Matthew 10:1, 5-8; Mark 6:7-13). Yet Judas later betrayed Christ. His ministry did not guarantee that he would remain faithful.
King Saul is another example. God chose him, gave him His Spirit, and Saul even prophesied (1 Samuel 10:6, 10). Later, because of his disobedience, the Spirit departed from him (1 Samuel 16:14). He began well but did not finish well.
Even Satan himself was created holy before becoming corrupt. A right beginning did not prevent a later fall.
Jesus gives the same warning in John 15. He describes branches that are in the vine but are later cut off because they do not continue to abide. The issue is not merely beginning with Christ, but remaining in Him.
So I agree that knowing Christ is the foundation. But according to Jesus, knowing Him and obeying Him cannot be separated. Obedience is not a substitute for a relationship with Christ, nor is a claimed relationship a substitute for obedience. Jesus consistently teaches that those who truly know Him hear His voice, follow Him, keep His commandments, abide in Him, bear good fruit, do the Father's will, and endure to the end. That is exactly what the context of Matthew 7 teaches.
Blessings
