Those who remember God, will be remembered  -  Malachi 3:16

Then they that feared the LORD spake often one to another: and the LORD hearkened, and heard it, and a book of remembrance was written before him for them that feared the LORD, and that thought upon his name.

There will always be a remnant of people that are true to God. They may be a small group but because they remember God, He will remember them.