The road must be trod, but it will be very hard. And neither strength nor wisdom will carry us far upon it. This quest may be attempted by the weak with as much hope as the strong. Yet such is oft the course of deeds that move the wheels of the world: small hands do them because they must, while the eyes of the great are elsewhere.

J.R.R. Tolkien (1892-1973) English writer, fabulist, philologist, academic [John Ronald Reuel Tolkien]

The Lord of the Rings, Vol. 1: The Fellowship of the Ring, Book 2, ch. 2 “The Council of Elrond” [Elrond] (1954)
    (Source)

Possibly the origin of the spurious "Even the smallest person can change the course of the future." This is said by Galadriel, but only in the film version, The Fellowship of the Ring (2001), screenplay by Fran Wash and Philippa Boyens.

More discussion: Not a Tolkien quote: "Even the smallest person can change the course of the future." - thetolkienist.com.