3) By failing to overcoming self and sin: Rev 2:11, Rev 3:5, 3:11-12, 3:21, 2Pet2:20-22
Rev 2:11 He that hath an ear, let him hear what the Spirit saith unto the churches; He that overcometh shall not be hurt of the second death.
Rev 3:5 He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.
Rev 3:11-12 Behold, I come quickly: hold that fast which thou hast, that no man take thy crown. (12) Him that overcometh will I make a pillar in the temple of my God, and he shall go no more out: and I will write upon him the name of my God, and the name of the city of my God, which is new Jerusalem, which cometh down out of heaven from my God: and I will write upon him my new name.
Rev 3:21 To him that overcometh will I grant to sit with me in my throne, even as I also overcame, and am set down with my Father in his throne.
2Pe 2:21-22 For it had been better for them not to have known the way of righteousness, than, after they have known it, to turn from the holy commandment delivered unto them. (22) But it is happened unto them according to the true proverb, The dog is turned to his own vomit again; and the sow that was washed to her wallowing in the mire.
4)By being unmerciful: Matt 5:7, Matt 6:14-15, Matt 18:33-35, Jas 2:13
Mat 5:7 Blessed are the merciful: for they shall obtain mercy.
Mat 6:14-15 For if ye forgive men their trespasses, your heavenly Father will also forgive you: (15) But if ye forgive not men their trespasses, neither will your Father forgive your trespasses.
Mat 18:30-35 And he would not: but went and cast him into prison, till he should pay the debt. (31) So when his fellowservants saw what was done, they were very sorry, and came and told unto their lord all that was done. (32) Then his lord, after that he had called him, said unto him, O thou wicked servant, I forgave thee all that debt, because thou desiredst me: (33) Shouldest not thou also have had compassion on thy fellow servant, even as I had pity on thee? (34) And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him. (35) So likewise shall my heavenly Father do also unto you, if ye from your hearts forgive not every one his brother their trespasses.
Jam 2:13 For he shall have judgment without mercy, that hath showed no mercy; and mercy rejoiceth against judgment.
5) By not continuing in the faith: Acts 14:22, John 8:31,32, John 15:4-6, Matt 10:38, Luke 22:28,29, 2 Peter 1:11.
Act 14:22 Confirming the souls of the disciples, and exhorting them to continue in the faith, and that we must through much tribulation enter into the kingdom of God.
Joh 8:31-32 Then said Jesus to those Jews which believed on him, If ye continue in my word, then are ye my disciples indeed; (32) And ye shall know the truth, and the truth shall make you free.
Joh 15:4-5 Abide in me, and I in you. As the branch cannot bear fruit of itself, except it abide in the vine; no more can ye, except ye abide in me. (5) I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.
Mat 10:38 And he that taketh not his cross, and followeth after me, is not worthy of me.
Luk 22:29-30 And I appoint unto you a kingdom, as my Father hath appointed unto me; (30) That ye may eat and drink at my table in my kingdom, and sit on thrones judging the twelve tribes of Israel.
2Pe 1:11 For so an entrance shall be ministered unto you abundantly into the everlasting kingdom of our Lord and Savior Jesus Christ.
That ought to keep you busy for a while. Just a challenge though: Read these verses and consider the possibility (that when they tell a believer to be good because the unrighteous won't inherit the Kingdom) that the verses mean exactly what they say.
Lacy