Zacchaeus was small of stature. There are many people of all sizes who are small-hearted, petty, little people. They have trouble seeing Jesus, for they have trouble seeing beyond themselves.
Zacchaeus was unable to see Jesus because of the crowd (Lk 19:3). Greed, pride, hypocrisy, and lukewarmness (Rv 3:16) can crowd us out of seeing Jesus.
Zacchaeus overcame his smallness and the crowd by climbing a tree (Lk 19:4). Be like a tree upon which people can climb to rise above their smallness and the obstructions of the crowd.
The Lord says we become "like a tree" when we delight "in the law of the Lord" and meditate "on His law day and night" (Ps 1:2, 3). The person who loves and lives God's word is like a tree — the tree of life (see Gn 2:9), the tree that Jesus died on (Acts 13:29).
The poet Joyce Kilmer wrote: "Only God can make a tree." Only God can make us like trees which can give the Zacchaeuses of the world the opportunity to see the Savior. Make like a tree.