Rom 11:3 Lord, they have killed thy prophets, and digged down thine altars; and I am left alone, and they seek my life.
Rom 11:4 But what saith the answer of God unto him? I have reserved to myself seven thousand men, who have not bowed the knee to the image of Baal.
Rom 11:5 Even so then at this present time also there is a remnant according to the election of grace.
A remnant is saved
Revelation 14:v.1-3
1 And I looked, and, lo, a Lamb stood on the mount Sion, and with Him an hundred forty and four thousand, having his Father's name written in their foreheads.
2 And I heard a voice from heaven, as the voice of many waters, and as the voice of a great thunder: and I heard the voice of harpers harping with their harps:
3 And they sung as it were a new song before the throne, and before the four living beings, and the elders: and no man could learn that song but the hundred and forty and four thousand, which were REDEEMED from the earth.
In the Elijah's time there were only seven thousand true Israelite and now, in the end of Dispensation of Grace, only 144k will be sealed and saved because believe in JESUS and love Him, in LITERAL fulfillment of Isaiah 1:v.8-9, among others.
Revelation 7:v.1-4
1 And after these things (things written in Rev.6:v.14 to 17) I saw four angels standing on the four corners of the earth, holding the four winds of the earth, that the wind should not blow on the earth, nor on the sea, nor on any tree.
2 And I saw another angel ascending from the east, having the seal of the living God: and he cried with a loud voice to the four angels, to whom it was given to hurt the earth and the sea,
3 Saying, Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads.
4 And I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand of all the tribes of the children of Israel.