Malachi 3:14, 15
You have said, It is vain to serve God: and what profit is it that we have kept his ordinance…
It is vain to serve God.' The Prophet Zephaniah is more severe. "It shall come to pass at that time, that I will search Jerusalem with candles, and punish the men that are settled on their lees: that say in their heart, The Lord will not do good, neither will he do evil" (Zephaniah 1:12). "The prophet condescends to identify himself with those whom he reproves. 'We call the proud happy; yea, we say, they that work wickedness are set up. Therefore it is vain to serve God.' But he suddenly quits the seat of the scorners. He retires aside from the crowd, who proudly rely on their own popular verdicts, vaunting their own intelligence, and setting at naught the decrees of God; and, standing aloft from them, he joins the smaller company of the faithful few who wait and fear the Lord, and think upon his Name."
I. THE SIN OF SERVING GOD FOR THE SAKE OF PROFIT. This is seen in the case of Ananias and of Simon Magus. It is illustrated by Bunyan, in his character of Pliable, the man who was going on pilgrimage for the sake of what he could get. God asks for the service of love. Such service as alone can please him is the service rendered under the impulse of love. It is not possible to serve God acceptably in the spirit of the hireling. It is equally true that God cannot be rightly served under the expectation of pay or reward in the next life.
II. THE SIN OF DOUBTING WHETHER GOD REWARDS SERVICE. It is the sin of unbelief. "He who comes to God must believe that he is, and that he is the Rewarder of them that diligently seek him." But it really is a deeper and a more subtle sin than that; it is the sin of self-centredness. Only the man who thinks overmuch about himself questions whether his work will be fittingly recognized. This is a constant secret sin, even of good people. They never master it until they can learn of Christ to work for love, and let rewards come or not as they may. A man never conceives of Divine indifference, or hardness, or unreasonableness, until he gets into a bad frame of mind himself, and then he makes God the shadow of his own badness. It was thus with the persons whom Malachi reproves. Only because they wanted to serve themselves did they think it was vain to serve God. The man who loves God and wants to serve him is sure never to think that.
III. THE SIN OF THINKING THOSE ARE REWARDED WHO SERVE OTHERS AND NOT GOD. (Ver. 15.) The proud, who serve themselves. Good people, like the poet Asaph, are often tempted to think that the wicked have the best of it in this life. To think so is to "offend against the generation of the upright," and to dishonour God, - R.T.
Parallel VersesKJV: Ye have said, It is vain to serve God: and what profit is it that we have kept his ordinance, and that we have walked mournfully before the LORD of hosts?