Luke 13
23 And someone said to him, "Lord, will those who are saved be few?" And he said to them, 24 "Strive to enter through the narrow door. For many, I tell you, will seek to enter and will not be able. 25 When once the master of the house has risen and shut the door, and you begin to stand outside and to knock at the door, saying, 'Lord, open to us,' then he will answer you, 'I do not know where you come from.' 26 Then you will begin to say, 'We ate and drank in your presence, and you taught in our streets.' 27 But he will say, 'I tell you, I do not know where you come from. Depart from me, all you workers of evil!' 28 In that place there will be weeping and gnashing of teeth, when you see Abraham and Isaac and Jacob and all the prophets in the kingdom of God but you yourselves cast out. 29 And people will come from east and west, and from north and south, and recline at table in the kingdom of God.
It seems that the immediate context of this is the judgement, or the end of the age. The door is shut when Jesus comes back and separates the sheep from the goats. If one is still breathing air on this earth, they are not reprobate, and Jesus has not returned yet, I don't see any reason to believe that the door has been shut on them yet. From a human perspective, there is still hope for them.
Likewise:
Matthew 25
1 "Then the kingdom of heaven will be like ten virgins who took their lamps and went to meet the bridegroom. 2 Five of them were foolish, and five were wise. 3 For when the foolish took their lamps, they took no oil with them, 4 but the wise took flasks of oil with their lamps. 5 As the bridegroom was delayed, they all became drowsy and slept. 6 But at midnight there was a cry, 'Here is the bridegroom! Come out to meet him.' 7 Then all those virgins rose and trimmed their lamps. 8 And the foolish said to the wise, 'Give us some of your oil, for our lamps are going out.' 9 But the wise answered, saying, 'Since there will not be enough for us and for you, go rather to the dealers and buy for yourselves.' 10 And while they were going to buy, the bridegroom came, and those who were ready went in with him to the marriage feast, and the door was shut. 11 Afterward the other virgins came also, saying, 'Lord, lord, open to us.' 12 But he answered, 'Truly, I say to you, I do not know you.' 13 Watch therefore, for you know neither the day nor the hour.
Once again, the door is shut when Jesus returns. Jesus warns us at the end of that parable, Watch therefore, for you know neither the day nor the hour. The day nor the hour of what? Christ's return, thats what. The door will be shut at Christ's return.
Hebrews 3
15 While it is said, To day if ye will hear his voice, harden not your hearts, as in the provocation. 16 For some, when they had heard, did provoke: howbeit not all that came out of Egypt by Moses. 17 But with whom was he grieved forty years? [was it] not with them that had sinned, whose carcases fell in the wilderness? 18 And to whom sware he that they should not enter into his rest, but to them that believed not? 19 So we see that they could not enter in because of unbelief.
Today is the day of salvation. If you hear his voice today, do not harden your hearts, but believe on the Lord Jesus Christ. One cannot believe in the Lord without repenting. One must always forsake what they had been clinging to in order to fully embrace the Lord. One cannot turn to God and cling to their idols at the same time. It's always one or the other. Believe on the Lord Jesus Christ, and thou wilt be saved. All who reside in unbelief will have the door shut on them and will exist in eternity separated from God.
Grace to you,
Travis