Romans 4:16-18

All depends on faith, and for this reason--that acceptance with God might be an act of pure grace,

Hebrews 11:12

And thus there sprang from one man, and him practically dead, a nation like the stars of the sky in number, and like the sands on the sea shore which cannot be counted.

Revelation 7:9

After this I looked, and a vast host appeared which it was impossible for anyone to count, gathered out of every nation and from all tribes and peoples and languages, standing before the throne and before the Lamb, clothed in long white robes, and carrying palm-branches in their hands.

Treasury of Scripture Knowledge

Summary

And I will make thy seed as the dust of the earth: so that if a man can number the dust of the earth, then shall thy seed also be numbered.

Bible References

General references

Romans 4:16
All depends on faith, and for this reason--that acceptance with God might be an act of pure grace,
Hebrews 11:12
And thus there sprang from one man, and him practically dead, a nation like the stars of the sky in number, and like the sands on the sea shore which cannot be counted.
Revelation 7:9
After this I looked, and a vast host appeared which it was impossible for anyone to count, gathered out of every nation and from all tribes and peoples and languages, standing before the throne and before the Lamb, clothed in long white robes, and carrying palm-branches in their hands.