Hundred
It's a landmark for a young child to count to 100; it sort of covers all the "ordinary" numbers. One hundred is obviously significant for other groupings: 100 cents is a dollar; 100 yards is a touchdown; 100 years is a century, and the landmark for a very long life. It makes sense, then, that in the Bible, 100 represents fullness or a state of completion, or in some instances simply "much." For instance, people marvel that Abraham had Isaac when he was 100 years old; the number represents the point at which the Lord, when growing up as Jesus, united the human elements of himself with the divine elements and in a sense became "complete.
Isaiah 51:1-3
1
"Listen to me, you who follow after righteousness, you who seek Yahweh: look to the rock you were cut from, and to the hold of the pit you were dug from.
2
Look to Abraham your father, and to Sarah who bore you; for when he was but one I called him, and I blessed him, and made him many.
3
For Yahweh has comforted Zion; he has comforted all her waste places, and has made her wilderness like Eden, and her desert like the garden of Yahweh; joy and gladness shall be found therein, thanksgiving, and the voice of melody.
