Matthew 24:3 And as he sat upon the mount of Olives, the disciples came unto him privately, saying, Tell us, when shall these things be? and what shall be the sign of thy coming, and of the end of the world?
Jesus is teaching the disciples of his coming and the time of Jacob's trouble, the tribulation. Jeremiah 30:7
24:13 But he that shall endure unto the end, the same shall be saved.
It is Israel that will be saved. Israel must endure til the end of the tribulation, but will be delivered out of it by the coming of the Lord Jesus Christ.
24:14 And this gospel of the kingdom shall be preached in all the world for a witness unto all nations; and then shall the end come.
The gospel of the kingdom is preached. The gospel of the coming Davidic kingdom on earth promised Israel.
24:21 For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.
24:22 And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened.
The elect is Israel.
24:29 Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:
This is the Day of the Lord. This is the great day of God's wrath, and the hope of Israel, that follows right after the tribulation. Isaiah 13:9-10 Joel 3:14-15
24:30 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.
24:31 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.
Believing Israel is the gathered elect.
24:34 Verily I say unto you, This generation shall not pass, till all these things be fulfilled.
Jesus was not speaking of the generation present at this time, but rather, the future generation at the end.
24:40 Then shall two be in the field; the one shall be taken, and the other left.
24:41 Two women shall be grinding at the mill; the one shall be taken, and the other left.
One taken, the other left is not the "rapture" of the church, but rather, the coming of the Lord Jesus Christ when His enemies will be slain. Revelation 19:19-21 Luke 17:35-37 Matthew 24:28
24:42 Watch therefore: for ye know not what hour your Lord doth come.
24:44 Therefore be ye also ready: for in such an hour as ye think not the Son of man cometh.
Israel was to be vigilant, in watching for, and being prepared for the Lord's coming.
24:45 Who then is a faithful and wise servant, whom his lord hath made ruler over his household, to give them meat in due season?
24:46 Blessed is that servant, whom his lord when he cometh shall find so doing.
24:47 Verily I say unto you, That he shall make him ruler over all his goods.
The little flock of Israel, the believing remnant, will be given positions of authority in the kingdom on earth during the thousand year reign of Christ. Luke 19:17 Revelation 5:10 Revelation 20:4
24:48 But and if that evil servant shall say in his heart, My lord delayeth his coming;
24:49 And shall begin to smite his fellowservants, and to eat and drink with the drunken;
24:50 The lord of that servant shall come in a day when he looketh not for him, and in an hour that he is not aware of,
24:51 And shall cut him asunder, and appoint him his portion with the hypocrites: there shall be weeping and gnashing of teeth.
The unprofitable servant will not enter the kingdom. That servant will be assigned to outer darkness, among the hypocrites. These servants however, are not going to hell. Luke 13:28 Matthew 13:41-42