Dr. David Martyn Lloyd-Jones:
You remember the resounding sentence at the end of the eight chapter of this Epistle to the Romans: ‘I am persuaded, that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come, nor height, nor depth, nor any other creature, shall be able to separate us from the of God, which is in Christ Jesus our Lord.’ ‘That is it’, says someone. ‘That’s the sort of thing I like. Why don’t you rush on to that? That is the thing to stabilize us!’ Ah, but wait a minute! The Apostle Paul is only able to make that statement because of all the things that he has been saying in his earlier chapters before he arrives at that statement! That is the conclusion of the mighty argument about justification and sanctification, and glorification. You cannot start with that. You end with it. And you will never be able to say that from your heart unless you really know, experimentally, these great doctrines. You must know them with your mind, you must experience them.
Volume 1 of Romans, pages 228-229.