What is the difference between tribulation and the wrath of God?
Tribulation is the trial of the saints through persecution, affliction, and hardship that produces patience and faith, while the wrath of God is His vengeance and judgment poured out specifically on the wicked, unrepentant world, not on His people.
Scripture draws a clear line between tribulation and the wrath of God. Tribulation refers to trial after trial, persecution, affliction, and reproach that the saints endure at the hands of the Antichrist and a hostile world. This suffering has a purpose: it works patience in the people of God and manifests their faith even in the face of death, as seen in the saints' endurance during the reign of the Antichrist. Revelation 13:7-10 shows the saints being overcome and even killed, yet it is called the patience and faith of the saints, not the wrath of God.
The wrath of God, by contrast, is the outpouring of His righteous indignation, judgment, and vengeance specifically upon the wicked and unrepentant who dwell on the earth. Romans 1:18 declares that this wrath is revealed from heaven against ungodliness, and it is not something orchestrated by human wars or devices; it is the Lord's own judgment. Revelation 15:1 identifies the wrath of God as being contained in the seven last plagues, which come after the one-world government of the Antichrist and the days of the mark of the beast.
The key difference, then, is the target and the timing. Tribulation is the trying of the saints through persecution and affliction, while wrath is the vengeance of God poured out on the wicked. Because God hath not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ (1 Thessalonians 5:9), the Church is not the object of this wrath, even though believers may pass through the tribulation caused by the Antichrist.
This distinction is also seen in how the trumpet judgments and vial judgments are separated. The trumpet judgments are described as the sorrows Jesus foretold, times when the church is still present on earth, still testifying, and still being tried. The vial judgments, however, are specifically deemed the wrath of God, poured out only after the church has been removed. So tribulation belongs to the season when the saints are still being tested on earth, while the wrath of God belongs to the season when judgment falls exclusively on those who remain in rebellion against Him.
The scriptures
For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold the truth in unrighteousness;
And I saw another sign in heaven, great and marvellous, seven angels having the seven last plagues; for in them is filled up the wrath of God.
And it was given unto him to make war with the saints, and to overcome them: and power was given him over all kindreds, and tongues, and nations. And all that dwell upon the earth shall worship him, whose names are not written in the book of life of the Lamb slain from the foundation of the world. If any man have an ear, let him hear. He that leadeth into captivity shall go into captivity: he that killeth with the sword must be killed with the sword. Here is the patience and the faith of the saints.
For God hath not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ,
I will utterly consume all things from off the land, saith the LORD. I will consume man and beast; I will consume the fowls of the heaven, and the fishes of the sea, and the stumbling blocks with the wicked: and I will cut off man from off the land, saith the LORD.
From the books
This answer is drawn from these passages in the Mary Banks Faith Library.