“I will be to them a God, and they [believers in Jesus, the Messiah] shall be to Me a people” (Hebrews 8:10).
The Old Covenant
…There were two great defects in that old covenant, which arose out of the weakness of poor human nature;
in the first place, it gave no power, no moral dynamics, to enable the human covenanters to do what they promised; and,
secondly, it could not provide for the effectual putting away of those sins which arose from their failure to carry into effect their covenanted vows (Heb. 9:9).
Surely the majority of men, aiming after a religious life, pass through an experience like this. When first we are redeemed by the blood of the Lamb, and brought out into the new life, we seem to stand again under Mount Sinai; or, better still, our conscience becomes our Sinai, and from its highest point we seem to hear the voice of God, engaging himself to be a God to us if we will in all things obey his voice. And this we immediately pledge ourselves to do. We are not insincere, we really mean to perform it; we are enamoured at the ideal of life presented to us. It is not only desirable as the condition of blessings, but it is eminently attractive and lovely.
But we make a profound mistake in pledging ourselves; for we are undertaking a matter which is totally beyond our reach. As well might a paralyzed man undertake to climb Mount Blanc, or a bankrupt to pay his debts. We soon learn that sin has paralyzed all our moral motor nerves. The good we would, we do not: the evil we would not, we do. We are brought into captivity to the law of sin in our members, which wars against the law of our mind. We go out to shake ourselves, as at other times; but we wist not that razors have passed over our locks of strength, leaving us powerless and helpless.
It seems a pity that each has to learn the uselessness of these attempts for himself, instead of profiting by the experience of others and the records of the past. Yet so it is. One after another starts to earn the privilege of God’s presence and smile and blessing by being good and obedient and punctilious in complying with rules and forms and regulations. It goes on well for a little while, but soon utterly breaks down. We are baffled and beaten, as sea-fowl who dash themselves against a lighthouse tower in the storm, and then fall wounded into the yeasty foam beneath. We are slow to learn that, as we receive justification, so must we receive sanctification, from the hands of God as His free gift.
If any reader of these lines is trying to keep up a friendly relationship with God on this principle of try and do and keep, the sooner that soul realizes the certainty of failure, not for want [lack] of will, but through the weakness of the moral nature, and yields itself to the grace revealed in the second and better covenant, the more quickly will it find a secure and happy resting place, from which it will not be disturbed or driven, world without end.
[ “For we through the Spirit eagerly wait for the hope of righteousness by faith. For in Christ Jesus neither circumcision nor uncircumcision avails anything, but faith working through love.” Gal. 5:5,6]
F.B. Meyer (1847-1929) from, The Way into the Holiest (an exposition of the Epistle to the Hebrews), ch. 19. Italics added.
 An allusion to Samson’s loss of strength (Judges 16:20). See the description of self effort under legalism in Romans 7:15-18.
 punctilious adj. “Strictly attentive to minute details of form in action or conduct.” http://www.thefreedictionary.com