Hebrews 11:12

so that even a single person whose vigour was gone, gave rise to a posterity as numerous as the stars of the sky, or the sands on the sea-shore, which cannot be numbred.

Revelation 7:9-10

After this I beheld, and there was a great multitude, which no man could number, of every nation, tribe, people, and language, who stood before the throne, and before the lamb cloathed in white robes, having palms in their hands.

Treasury of Scripture Knowledge

Summary

As the host of heaven cannot be numbered, neither the sand of the sea measured: so will I multiply the seed of David my servant, and the Levites that minister unto me.

Bible References

The host

Hebrews 11:12
so that even a single person whose vigour was gone, gave rise to a posterity as numerous as the stars of the sky, or the sands on the sea-shore, which cannot be numbred.
Revelation 7:9
After this I beheld, and there was a great multitude, which no man could number, of every nation, tribe, people, and language, who stood before the throne, and before the lamb cloathed in white robes, having palms in their hands.