Alas! for that day is great, so that none is like it: it is even the time of Jacob's trouble, but he shall be saved out of it.
Here is SOP...
As the approach of the Roman armies was a sign to the disciples of the impending destruction of Jerusalem, so may this apostasy be a sign to us that the limit of God's forbearance is reached, that the measure of our nation's iniquity is full, and that the angel of mercy is about to take her flight, never to return. The people of God will then be plunged into those scenes of affliction and distress which prophets have described as the time of Jacob's trouble. The cries of the faithful, persecuted ones ascend to heaven. And as the blood of Abel cried from the ground, there are voices also crying to God from martyrs' graves, from the sepulchres of the sea, from mountain caverns, from convent vaults: "How long, O Lord, holy and true, dost Thou not judge and avenge our blood on them that dwell on the earth?" 5T 451
About four months since I had a vision of events all in the future. I saw the time of trouble, such as never was. Jesus told me it was the time of Jacob's trouble, and that we should be delivered out of it by the voice of God. Then I saw the four angels cease to hold the four winds. And I saw famine, pestilence and sword--nation rose against nation, and the whole world was in confusion. Then we cried to God day and night for deliverance, until we began to hear the bells on Jesus' garment. And I saw Jesus rise up in the Holiest, and as he came out we heard the tinkling of the bells and knew that our High Priest was coming out. Then we heard the voice of God which shook the heavens and the earth, and gave the 144,000 the day and hour of Jesus coming. Then the saints were free, united, and full of the glory of God, for he has turned their captivity. And I saw a flaming cloud come where Jesus' stood. Then Jesus laid off his priestly garment and put on his Kingly robe, and took his place on the cloud which carried him to the East, where it first appeared to the saints on earth--a small black cloud which was the sign of the Son of Man. While the cloud was passing from the Holiest to the East, which took a number of days, the synagogue of Satan worshipped at the saint's feet. Portland, April 6, 1846. BROADSIDE1 APR.06,1846
Jacob's experience during that night of wrestling and anguish represents the trial through which the people of God must pass just before Christ's second coming. The prophet Jeremiah, in holy vision looking down to this time, said, "We have heard a voice of trembling, of fear, and not of peace. . . . All faces are turned into paleness. Alas! for that day is great, so that none is like it: it is even the time of Jacob's trouble; but he shall be saved out of it." Jeremiah 30:5-7. PP 201
The path to freedom from sin is through crucifixion of self, and conflict with the powers of darkness. Let none be discouraged in view of the severe trials to be met in the time of Jacob's trouble, which is yet before them. They are to work earnestly, anxiously, not for that time, but for to-day. What we want is to have a knowledge of the truth as it is in Christ now, and a personal experience now. In these precious closing hours of probation, we have a deep and living experience to gain. We shall thus form characters that will insure our deliverance in the time of trouble. RH AUG.12,1884
As the members of the body of Christ approach the period of their last conflict, "the time of Jacob's trouble," they will grow up into Christ, and will partake largely of his Spirit. As the third message swells to a loud cry, and as great power and glory attends the closing work, the faithful people of God will partake of that glory. It is the latter rain which revives and strengthens them to pass through the time of trouble. Their faces will shine with the glory of that light which attends the third angel. RH MAY 27,1862
This, will be the time of Jacob's trouble, (Jer. 30:5-8) out of which, the saints will be delivered by the voice of God. WLF 12
A Crisis Makes God's Interference More Marked
From time to time the Lord has made known His manner of working. He is mindful of what is passing upon the earth. And when a crisis has come, He has revealed Himself and has interposed to hinder the working of Satan's plans. He has often permitted matters with nations, with families, and with individuals to come to a crisis that His interference might become marked. Then He has let the fact be known that there was a God in Israel who would sustain and vindicate His people.
When the defiance of the law of Jehovah shall be almost universal, when His people shall be pressed in affliction by their fellow men, God will interpose. The fervent prayers of His people will be answered, for He loves to have His people seek Him with all their heart and depend upon Him as their Deliverer.--RH June 15, 1897.
For a time the oppressors will be permitted to triumph over those who know God's holy commandments. . . . To the last, God permits Satan to reveal his character as a liar, an accuser, and a murderer. Thus the final triumph of His people is made more marked, more glorious, more full and complete.--3SM 414 (1904).
Affliction Purifies God's People
Soon there is to be trouble all over the world. It becomes everyone to seek to know God. We have no time to delay. . . .
God's love for His church is infinite. His care over His heritage is unceasing. He suffers no affliction to come upon the church but such as is essential for her purification, her present and eternal good. He will purify His church even as He purified the temple at the beginning and close of His ministry on earth. All that He brings upon the church in test and trial comes that His people may gain deeper piety and more strength to carry the triumphs of the cross to all parts of the world.--9T 228 (1909).
Afflictions, crosses, temptations, adversity, and our varied trials are God's workmen to refine us, sanctify us, and fit us for the heavenly garner.--3T 115 (1872).https://www.ellenwhitedefend.com/Books-EGW/lde/lde10.htm