As of June 2018, a census showed that there were 2.5 million Messianic Jews worldwide, and their numbers continue to increase.
Messianic Jews Grow in the World in 2018 | Answers in Torah
“They were broken off because of unbelief, and you stand by faith. Do not be arrogant, but tremble.” (Romans 11:20)
“For since their rejection meant that God offered salvation to the rest of the world, their acceptance will be even more wonderful.” (Romans 11:15)
" I do not want you to be ignorant of this mystery, brothers, so that you will not be conceited: A hardening in part has come to Israel, until the full number of the Gentiles has come in. And so all Israel will be saved, as it is written, this is My covenant with them when I take away their sins.” (Romans 11:25-27)
“But Israel will be saved by the LORD with an everlasting salvation; you will not be put to shame or humiliated, to ages everlasting.” (Isaiah 45:17)
"This is what the Lord Almighty says: "In those days ten people from all languages and nations will take firm hold of one Jew by the hem of his robe and say, ‘Let us go with you, because we have heard that God is with you.’” (Zechariah 8:23)