Rashi on Deuteronomy 1:10/רש"י על דברים א׳:י׳

1והנכם היום ככוכבי השמים AND, BEHOLD, YE ARE THIS DAY AS THE STARS OF THE HEAVEN — But were they that day as the stars of the heaven? Were they not, indeed, only sixty myriads? What, then, is the meaning of “And, behold, ye are this day (היום lit., the day)"? It means: Behold ye may be compared to the day (the sun), existing for ever just as the sun and the moon and the stars (cf. Sifrei Devarim 10:1).