http://www.ccel.org/ccel/mcgarvey/gospels.vii.vii.html
3 Blessed are the poor in spirit: for theirs is the kingdom of heaven.
There must be emptiness before there can be fullness, and so poverty of spirit precedes riches and grace in the kingdom of God.
The commentary is extra-textural, of course, but I do like the line here. It’s just one of those “obvious” statements that is obvious after you read it, not always before.