On Loving God, by St Bernard of Clairvaux ~ Chapter 14: Of the Law of the Love of Sons.

Now the children have their law, even though it is written, 'The law is not made for a righteous man' (I Tim. 1.9). For it must be remembered that there is one law having to do with the spirit of servitude, given to fear, and another with the spirit of liberty, given in tenderness.

The children are not constrained by the first, yet they could not exist without the second: even as St. Paul writes, 'Ye have not received the spirit of bondage again to fear; but ye have received the spirit of adoption, whereby we cry, Abba, Father' (Rom. 8.15). And again to show that that same righteous man was not under the law, he says: 'To them that are under the law, I became as under the law, that I might gain them that are under the law; to them that are without law, as without law (being not without law to God, but under the law to Christ)' (I Cor. 9.20f).

So it is rightly said, not that the righteous do not have a law, but, 'The law is not made for a righteous man', that is, it is not imposed on rebels but freely given to those willingly obedient, by Him whose goodness established it. Wherefore the Lord saith meekly: 'Take My yoke upon you', which may be paraphrased thus: 'I do not force it on you, if you are reluctant; but if you will you may bear it. Otherwise it will be weariness, not rest, that you shall find for your souls.'

Love is a good and pleasant law; it is not only easy to bear, but it makes the laws of slaves and hirelings tolerable; not destroying but completing them; as the Lord saith: 'I am not come to destroy the law, but to fulfill' (Matt. 5.17). It tempers the fear of the slave, it regulates the desires of the hireling, it mitigates the severity of each. Love is never without fear, but it is godly fear. Love is never without desire, but it is lawful desire. So love perfects the law of service by infusing devotion; it perfects the law of wages by restraining covetousness. Devotion mixed with fear does not destroy it, but purges it.

Then the burden of fear which was intolerable while it was only servile, becomes tolerable; and the fear itself remains ever pure and filial. For though we read: 'Perfect love casteth out fear' (I John 4.18), we understand by that the suffering which is never absent from servile fear, the cause being put for the effect, as often elsewhere. So, too, self-interest is restrained within due bounds when love supervenes; for then it rejects evil things altogether, prefers better things to those merely good, and cares for the good only on account of the better.

In like manner, by God's grace, it will come about that man will love his body and all things pertaining to his body, for the sake of his soul. He will love his soul for God's sake; and he will love God for Himself alone.