COULD NOT
"Have not kept his commandments" - What is not but the chief characteristic of one who is called of God is but those who follow the commandments of God. Jesus Christ said "if you love me keep my commandments." And also it says in Scripture: "For this is the love of God that we keep his commandments: and his commandments are not grievous."
Calvin accurately expounds on this warning from God: "But we must notice the explanation which immediately follows - that 'they kept not his statutes'. The way then by which Amos proves that the Jews were covenant-breakers, and that having repudiated God's law, they had fallen into wicked superstitions, is by saying, that they kept not the precepts of God.
It may, however, appear that he treats them here with too much severity; for one might not altogether keep God's commands either through ignorance or carelessness, or some other fault, and ye be not a covenant-breaker or an apostate.
I answer - That in these words of the Prophet, not mere negligence is blamed in the Jews; but they are condemned for designedly, that is, knowingly and willfully departing from the commandments of God, and devising for themselves various modes of worship.
It is not then to keep the precepts of God, when men continue not under his law, but audaciously contrive for themselves new forms of worship; they regard not what God commands, but lay hold on anything pleasing that comes to their minds."
J.C. Ryle speaks on keeping the commandments of God:
"In the last place, let us beware of supposing that the Gospel has lowered the standard of personal holiness, and that the Christian is not intended to be as strict and particular about his daily life as the Jew. This is an immense mistake, but one that is unhappily very common.
So far from this being the case, the sanctification of the New Testament saint ought to exceed that of him who has nothing but the Old Testament for his guide. The more light we have, the more we ought to love God: the more clearly we see our own complete and full forgiveness in Christ, the more heartily ought we to work for His glory.
We know what is the cost to redeem us far better then the Old Testament saints did. We have read what happened in Gethsemane and on Calvary, and they only saw it dimly and indistinctly as a thing yet to come. May we never forget our obligations!The Christian who is content with a low standard of personal holiness has got much to learn."
May we be of those that keep "the commandments of God" Church! Israel "could not" keep the commands of God but we "can" keep the commands through the power of God.
WOULD NOT
"Their lies caused them to err" - Oh, how often we are led astray by false idols and gods that we exalt in our lives. How deceived we can become being "believers" yet walking in "unbelief" and carnality.
John Calvin again shows how Israel erred in walking in deception with pretense that they were walking with God: "But he also adds, that 'their own lies deceived or caused them to go astray'. He here confirms his preceding doctrine; for the Jews had ever a defense ready at hand, that they did with good intent what the Prophet condemned in them.
They, in truth persistently worshiped God, though they mixed their own leaven, by which their sacrifices were corrupted: it was not their purpose to spend their substance in vain, to undergo great expenses in sacrifices, and to undertake much labour, had they not thought that it was service acceptable to God!
As then the pretense of good intention (as they say) ever deceives the unbelieving, the Prophet condemns this pretense, and shows it to be wholly fallacious, and of no avail. 'It is nothing,' he says, 'that they pretend before God some good intention; their own lies deceive them.'"
Israel in it's day "would not" walk in the ways of God and the Church in our day is following that path of deception. Israel believed they were following God but it was a farce and deception. They would not walk in the ways that were right and found the lack of power to do so. God desires His Church to walk worthy of the gospel of the Lord Jesus Christ.
May we not do as Israel of old did: "But ye gave the Nazarites wine to drink; and commanded the prophets, saying, Prophesy not." What a terrible day it is when the "voice of God" is being dampened by the voices of mere men. We need to take off the veil of "pretense" before God and be honest before Him of our need to hear from Him in these perilous hours of the Church age.
"For the grace of God that bringeth salvation hath appeared to all men. Teaching us that, denying ungodliness and worldly lusts, we should live soberly, righteously, and godly in this present world. Looking for that blessed hope, and the glorious appearing of the great God and our Saviour Jesus Christ; who gave Himself for us, that he might redeem us from all iniquity..." (Titus 2:11-14a).