Regarding Malachi 2:17 Malachi 2:17You have wearied the LORD with your words. Yet you say, Wherein have we wearied him? When you say, Every one that does evil is good in the sight of the LORD, and he delights in them; or, Where is the God of judgment?
American King James Version×, Charles Feinberg states in his book The Minor Prophets: “The third offence of the ungodly in Israel was an evil skepticism. By their ungodliness and unbelief they had wearied God; they had exhausted his patience [and still they again are quick to retort with "In what way…?"]. They brought forward the old argument against the providence of God from the prosperity of the wicked and the suffering of the righteous. They had endured so many trials in exilic and postexilic times, that they were ready to believe that God delighted in and favored the cause of the wicked, the heathen who enjoyed prosperity, over against the ungodly.
"They complained that God did not judge wickedness severely enough. And if such were not the case, where indeed is the God of justice of whom they heard continually. Many connect this verse with the next chapter (and it is related in thought), because the answer to Malachi 2:17 is found in Malachi 3:1 Malachi 3:1Behold, I will send my messenger, and he shall prepare the way before me: and the LORD, whom you seek, shall suddenly come to his temple, even the messenger of the covenant, whom you delight in: behold, he shall come, said the LORD of hosts.
American King James Version×[or, rather, starts in 3:1 and continues through chapter 4 in the description of the coming Day of the Lord]. God never fails to answer such a question put forth in such skeptical spirit. It rounded out the tale of their misdeeds and revealed them to be ripe for judgment" (pp. 258-259).
In Malachi 3:1 Malachi 3:1Behold, I will send my messenger, and he shall prepare the way before me: and the LORD, whom you seek, shall suddenly come to his temple, even the messenger of the covenant, whom you delight in: behold, he shall come, said the LORD of hosts.
American King James Version×, God says, "Behold, I send My messenger, and he will prepare the way before Me." The beginning of this verse could also be translated as "Behold, I send Malachi…" Certainly, the work of Malachi, God's messenger, was one of preparing the people for the coming of God—and His work continues even today, for his words are so preparing us who read and respond to them. Yet the reference, as the New Testament explains, was more directly to another, John the Baptist (Matthew 11:10 Matthew 11:10For this is he, of whom it is written, Behold, I send my messenger before your face, which shall prepare your way before you.
American King James Version×; Mark 1:2 Mark 1:2As it is written in the prophets, Behold, I send my messenger before your face, which shall prepare your way before you.
American King James Version×; Luke 7:27 Luke 7:27This is he, of whom it is written, Behold, I send my messenger before your face, which shall prepare your way before you.
American King James Version×). The "Lord" whom the people sought was the long-promised Messiah. As the temple is said to be "His," we should understand Him to be the very God who was worshiped in it. Yet He Himself is also referred to as a messenger, having been sent by God the Father. He would come as "the Messenger of the covenant." He had presented the various covenants of the Old Testament, yet this probably refers to His coming to mediate the New Covenant.
"The phrase 'whom you [seek or] desire' [NIV] is interesting. Even in their sin, suggests 2:17, the people longed for deliverance through the Messiah. Amos, too, had people in his audience who 'desired' the Day of the Lord; but he bluntly told them that the Day of the Lord would be darkness and not light (Amos 5:19-20 Amos 5:19-20  As if a man did flee from a lion, and a bear met him; or went into the house, and leaned his hand on the wall, and a serpent bit him.
 Shall not the day of the LORD be darkness, and not light? even very dark, and no brightness in it?
American King James Version×). So, too, Malachi asked in 3:2, 'Who can endure the day of his coming?' The coming Messiah would bring judgment—viz., vindication and exoneration for the righteous but condemnation and punishment for the wicked" (Expositor's Bible Commentary,note on verse 1).
The question "But who can endure the day of His coming?" recalls Joel 2:11 Joel 2:11And the LORD shall utter his voice before his army: for his camp is very great: for he is strong that executes his word: for the day of the LORD is great and very terrible; and who can abide it?
American King James Version×: "For the day of the LORD [i.e., God] is great and very terrible; who can endure it?" This again identifies the messianic Messenger as being God. In this context, the question "Who can stand when He appears?"—essentially repeated in Revelation 6:17 Revelation 6:17For the great day of his wrath is come; and who shall be able to stand?
American King James Version×—also very clearly points to the coming of God. The likening of the Messenger to a refiner's fire and launderer's soap (Malachi 3:2 Malachi 3:2But who may abide the day of his coming? and who shall stand when he appears? for he is like a refiner's fire, and like fullers' soap:
American King James Version×) shows Him to be a purifier of His people. The reference to His being a refiner and purifier of silver, purging the sons of Levi so that they may offer acceptable offerings, recalls Isaiah 1, where God decried Israel's unacceptable worship and offerings (verses 10-15) and proclaimed, "Your silver has become dross…. I will turn My hand against you, and thoroughly purge away your dross" (verses 22, 25).
In Malachi 3:5 Malachi 3:5And I will come near to you to judgment; and I will be a swift witness against the sorcerers, and against the adulterers, and against false swearers, and against those that oppress the hireling in his wages, the widow, and the fatherless, and that turn aside the stranger from his right, and fear not me, said the LORD of hosts.
American King James Version×, the word translated "judgment" is probably better rendered "justice" here. That is, God will set the nation on the right track again and then actively intervene to righteously deal with those who don't follow His laws. Again, this is in answer to the issue of Malachi 2:17 Malachi 2:17You have wearied the LORD with your words. Yet you say, Wherein have we wearied him? When you say, Every one that does evil is good in the sight of the LORD, and he delights in them; or, Where is the God of judgment?
American King James Version×, where God is accused of rewarding evil.
Malachi 3:6 Malachi 3:6For I am the LORD, I change not; therefore you sons of Jacob are not consumed.
American King James Version×provides great comfort. God is not fickle. His character is always constant. It is because of this that the people of Israel, both physical and spiritual, are not consumed. Though they often deserve to be destroyed for their sins, God's great mercy and compassion, as well as the working out of His plan and purpose, are unswerving.
But God's faithfulness has not been returned in kind. So He encourages the people to "return"—that is, repent. Yet they don't see the need, now asking, "In what way shall we return?" (verse 7). God then gives them an example of their disobedience—stating that they have robbed Him. "In what way…?" they come back with again (verse 8). Then He makes clear that the issue is their failure to tithe and give offerings.
Holding back from God what rightfully belongs to Him amounts to stealing. This brought the people of Malachi's day under a curse. The modern nations descended from ancient Israel experience this curse even still. The Expositor's Bible Commentary notes: "Most churches still fall under this indictment [of robbing God]; their budgets are generally nowhere near 10 percent of the income of the members" (note on verse 9). And God's tithing law applies to all, not only to those who choose to attend church.
If people complied with God's laws in this regard, they would be greatly blessed. After paying tithes and giving offerings, God would help their remaining income stretch to cover all their needs and more. They would experience no lack of provisions. And there would be many tangible and intangible blessings besides (verses 10-12). Indeed, God told the people of Malachi's day—and all people since, including us—to test Him in this matter (verse 10). God will demonstrate His faithfulness by keeping His promise. We, of course, must make sure we are remaining faithful to Him.