Judge of All the Earth

Abraham calls God the "Judge of all the earth:"

“And Abraham came near and said, “Would You also destroy the righteous with the wicked?
“Suppose there were fifty righteous within the city; would You also destroy the place and not spare it for the fifty righteous that were in it?
“Far be it from You to do such a thing as this, to slay the righteous with the wicked, so that the righteous should be as the wicked; far be it from You! Shall not the Judge of all the earth do right?”
(Genesis 18:23-25).

One Judge	God Himself
Valley of Jehoshaphat	God the Father
God the Son	The Holy Spirit
Day of the Lord

One Judge

Though it is only a textual variant, many of the newer translations have this text for James 4:1:

"There is one lawgiver and judge who is able to save and to destroy. So who, then, are you to judge your neighbor?" (James 4:12 NRSV).

One God, one judge:

"For the LORD is our judge, the LORD is our lawgiver, the LORD is our king; he will save us." (Isaiah 33:22).

God Himself

God Himself is judge and not a surrogate:

"Let the heavens declare His righteousness, for God Himself is Judge. Selah." (Psalm 50:6);

"But God is the Judge: He puts down one, and exalts another." (Psalm 75:7);

"Let the rivers clap their hands; let the hills be joyful together before the LORD, for He is coming to judge the earth. With righteousness He shall judge the world, and the peoples with equity." (Psalm 98:8-9).

"For He is coming, for He is coming to judge the earth. He shall judge the world with righteousness, and the peoples with His truth." (Psalm 96:13).

That God will judge the world is both Old Testament doctrine and New Testament doctrine:

"But in accordance with your hardness and your impenitent heart you are treasuring up for yourself wrath in the day of wrath and revelation of the righteous judgment of God, who “will render to each one according to his deeds”: eternal life to those who by patient continuance in doing good seek for glory, honor, and immortality; but to those who are self-seeking and do not obey the truth, but obey unrighteousness—indignation and wrath, tribulation and anguish, on every soul of man who does evil. . ." (Romans 2:5-9).

The Valley of Jehoshaphat

Many Christians today do not believe in a Final Judgment, which is really a shame because the Bible doctrine is clear as a bell:

“Assemble and come, all you nations, and gather together all around. Cause Your mighty ones to go down there, O Lord.
“Let the nations be wakened, and come up to the Valley of Jehoshaphat; for there I will sit to judge all the surrounding nations.
“Put in the sickle, for the harvest is ripe. Come, go down; for the winepress is full, the vats overflow— for their wickedness is great.”

(Joel 3:11-13).

The event is simple, clearly defined, and sure to come:

"The person by whom God will judge the world, is his only-begotten Son, whose “goings forth are from everlasting;” “who is God over all, blessed for ever.” Unto Him, being “the outbeaming of his Father’s glory, the express image of his person,” (Hebrews 1:3,) the Father “hath committed all judgment, because he is the Son of Man;” (John 5:2, 27;) because, though he was “in the form of God, and thought it not robbery to be equal with God, yet he emptied himself, taking upon him the form of a servant, being made in the likeness of men;” (Philippians 2:6, 7;) yea, because, “being found in fashion as a man, he humbled himself” yet farther, “becoming obedient unto death, even the death of the cross. . .

"O, who can stand before the face of the great God, even our Savior Jesus Christ!

"See! See! He cometh! He maketh the clouds his chariots! He rideth upon the wings of the wind! A devouring fire goeth before him, and after him a flame burneth! See! He sitteth upon his throne, clothed with light as with a garment, arrayed with majesty and honor! Behold, his eyes are as a flame of fire, his voice as the sound of many waters!"

(John Wesley, The Great Assize, Sermon XV).

God the Father

Some verses ascribe judgment to God the Father: "And if ye call on the Father, who without respect of persons judgeth according to every man’s work, pass the time of your sojourning here in fear:. . ." (1 Peter 1:17). It is a remarkable feature of scripture that very many of God's distinctive works are ascribed variously to Father, Son, and Holy Spirit. We say, one of the Trinity became incarnate; but with many other divine attributes and activities, there is no such restriction.

God the Son

God the Son separates the sheep from the goats:

“When the Son of Man comes in His glory, and all the holy angels with Him, then He will sit on the throne of His glory. All the nations will be gathered before Him, and He will separate them one from another, as a shepherd divides his sheep from the goats. And He will set the sheep on His right hand, but the goats on the left.“ (Matthew 25:31-33).

God the Son is Judge:

“For the Father judgeth no man, but hath committed all judgment unto the Son: That all men should honour the Son, even as they honour the Father. He that honoureth not the Son honoureth not the Father which hath sent him.”
(John 5:23-24).

“But why dost thou judge thy brother? or why dost thou set at nought thy brother? for we shall all stand before the judgment seat of Christ.”
(Romans 14:10).

“And he commanded us to preach unto the people, and to testify that it is he which was ordained of God to be the Judge of quick and dead.”
(Acts 10:42).

“I charge you therefore before God and the Lord Jesus Christ, who will judge the living and the dead at His appearing and His kingdom: Preach the word! Be ready in season and out of season.”
(2 Timothy 4:1).

“For we must all appear before the judgment seat of Christ, that each one may receive the things done in the body, according to what he has done, whether good or bad.”
(2 Corinthians 5:10).

We shall all stand before this Judge on the last day:

"If it shall be a solemn thing to find ourselves face to face with the dead, how much more solemn to stand face to face with the great Judge both of the quick and dead. We have read — we have often thought of Jesus Christ, till we felt as if we saw him. . .When our dust revives, and the grave that is now awaiting us shall give up its dead, with these very eyes we shall see him — by the light of a world in flames we shall see him, a God enthroned for judgment." (Thomas Guthrie, The Gospel in Ezekiel, Kindle location 3917).

The Holy Spirit

There is a spirit of judgment, and spirit of burning known to scripture, which may well be the same Spirit Luke refers to, "John answered, saying unto them all, I indeed baptize you with water; but one mightier than I cometh, the latchet of whose shoes I am not worthy to unloose: he shall baptize you with the Holy Ghost and with fire:. . ." (Luke 3:16), the Holy Spirit:

"And it shall come to pass, that he that is left in Zion, and he that remaineth in Jerusalem, shall be called holy, even every one that is written among the living in Jerusalem: When the Lord shall have washed away the filth of the daughters of Zion, and shall have purged the blood of Jerusalem from the midst thereof by the spirit of judgment, and by the spirit of burning." (Isaiah 4:3-4).

Judgment involves Father, Son and Holy Spirit.

Day of the Lord

The Old Testament prophesies a 'Day of the Lord,' when sinners will be cast out of the land:

"Behold, the day of the Lord comes, cruel, with both wrath and fierce anger, to lay the land desolate; and He will destroy its sinners from it. For the stars of heaven and their constellations Will not give their light; the sun will be darkened in its going forth, and the moon will not cause its light to shine. “I will punish the world for its evil, and the wicked for their iniquity; I will halt the arrogance of the proud, and will lay low the haughtiness of the terrible." (Isaiah 13:9-11).

"Alas for the day! For the day of the Lord is at hand; it shall come as destruction from the Almighty." (Joel 1:15).

In some cases what is envisioned is some local judgment, but sometimes the Second Coming. In the New Testament, we read about "the day of our Lord Jesus Christ:

“I thank my God always concerning you for the grace of God which was given to you by Christ Jesus, that you were enriched in everything by Him in all utterance and all knowledge, even as the testimony of Christ was confirmed in you, so that you come short in no gift, eagerly waiting for the revelation of our Lord Jesus Christ, who will also confirm you to the end, that you may be blameless in the day of our Lord Jesus Christ.”
(1 Corinthians 1:4-8).

Now I trust you will understand, even to the end (as also you have understood us in part), that we are your boast as you also are ours, in the day of the Lord Jesus.
(2 Corinthians 1:13-14).

“Now, brethren, concerning the coming of our Lord Jesus Christ and our gathering together to Him, we ask you, not to be soon shaken in mind or troubled, either by spirit or by word or by letter, as if from us, as though the day of Christ had come.”
(2 Thessalonians 2:1-2).

“I thank my God upon every remembrance of you, always in every prayer of mine making request for you all with joy, for your fellowship in the gospel from the first day until now, being confident of this very thing, that He who has begun a good work in you will complete it until the day of Jesus Christ. . ." (Philippians 1:3-6).

These references to the 'Day of Christ' or 'Day of the Lord Jesus' suggest that the occasion is the very same one as referenced in the Old Testament texts, as is He whose advent is expected.