'Children' in the Bible

So we also, when we were children, were held in bondage under the rudiments of the world:

My little children, of whom I am again in travail until Christ be formed in you--

Which things contain an allegory: for these women are two covenants; one from mount Sinai, bearing children unto bondage, which is Hagar.

Now this Hagar is mount Sinai in Arabia and answereth to the Jerusalem that now is: for she is in bondage with her children.

For it is written, Rejoice, thou barren that bearest not; Break forth and cry, thou that travailest not: For more are the children of the desolate than of her that hath the husband.

Now we, brethren, as Isaac was, are children of promise.

Wherefore, brethren, we are not children of a handmaid, but of the freewoman.