This is one of those days (which are not rare!) when two of the readings from M’Cheyne’s plan go very well together. This passage from Isaiah 1 is the first of them. The Lord has been speaking through the prophet, lamenting that all their religion was an outward thing. Lots of sacrifices and incense (v 11), lots of wordy prayers (v 15), lots of festivals (v 14) but it was all hypocrisy. They had forgotten that they belonged to God and had forsaken Him (v 3-4). Their whole head was sick and their whole heart was faint. From head to foot they were wretched and an eyesore to God (v 6). They were overrun by enemies as a consequence and only a remnant was left (v 7-9). God was not going to listen to them and take pleasure in them until these offences were stopped and true religion flourished again - they needed to repent (v 16-17). And then comes the remarkable promise in verse 18 (see above). If the people would truly repent, the removal of the stain of their sin was possible. In fact, it would not only be removed but they would become spotlessly and dazzlingly clean!
We know, of course, that sin is a heart problem and that for the kind of cleansing that is spoken of here, there has to be a change of the heart towards God - it is clear that just going through the motions - drawing near with the lips but with hearts that were far away (as Israel was doing) wasn’t going to make anything better - in fact it was making things worse for them.
It is also clear that the Old Covenant sacrifices weren’t able to bring about this spotless purification of the heart. If they had done so, then the people would have had clean consciences and would not have needed the apparently endless repetition of blood sacrifices that were prescribed under that Covenant economy.
Obviously, heart-cleansing is possible - otherwise God would not have spoken about it through Isaiah. The question is, how?
And that is where another of the readings today provides the answer:
Hebrews 9:11–14 But when Christ appeared as a high priest of the good things that have come, then through the greater and more perfect tent (not made with hands, that is, not of this creation) 12 he entered once for all into the holy places, not by means of the blood of goats and calves but by means of his own blood, thus securing an eternal redemption. 13 For if the blood of goats and bulls, and the sprinkling of defiled persons with the ashes of a heifer, sanctify for the purification of the flesh, 14 how much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God.
Christ is the answer! He has made possible by His sacrifice what all those tens of thousands of animal sacrifices were unable to do - cleanse the consciences of those who draw near in faith! The blood of those sacrifices was taken from the altar into the presence of God in the Holy of Holies and was sprinkled there to make atonement for the people - but it had to be done again and again, as it only cleansed the flesh of the people. But the blood of Christ’s sacrifice - His own blood - He has taken into the presence of God in heaven itself - the true tabernacle of which the one on earth was but a man-made copy.
And note that He did this “once for all” (v 12). His is the sacrifice to end all sacrifices, because unlike them, His blood really does cleanse the conscience of the one who comes, turning from their sin and trusting in Him alone to save them. So His sacrifice doesn’t ever need to be repeated - “It is Finished!” as Jesus cried out triumphantly from the cross!
Back in Isaiah’s day, with eyes of faith, the people could see the coming Messiah through all the types and shadows of the Mosaic and the ceremonial laws. They could hear about Him in the words of the prophets (many of which speak of Jesus in remarkable detail and were written hundreds of years before He came). And their hearts were made as white as snow as they looked beyond the blood of the bulls and goats and put their trust in Christ and His shed blood, to Whom all of their sacrifices pointed.
And for us today, we can look back not only to the Old Covenant sacrifices, but to Jesus fulfilling them all as He hung on the cross. We can put our faith in the completed redemption that He has accomplished. And as we do so, abandoning our sin and laying hold on Christ alone, His blood is applied to our hearts and the stain of sin is wiped away - we become as white as snow. When we do this, we realize what countless generations of people have come to understand down through the ages as they have believed in Jesus:
There is a fountain filled with blood
Drawn from Immanuel's veins;
And sinners, plunged beneath that flood,
Lose all their guilty stains.
The dying thief rejoiced to see
That fountain in his day;
And there have I, though vile as he,
Washed all my sins away.
Dear dying Lamb, Thy precious blood
Shall never lose its pow'r,
Till all the ransomed Church of God
Be saved to sin no more.
E'er since by faith I saw the stream
Thy flowing wounds supply,
Redeeming love has been my theme,
And shall be till I die.
When this poor lisping, stamm'ring tongue
Lies silent in the grave,
Then in a nobler, sweeter song
I'll sing Thy pow'r to save.
