These three offices, Judge, Advocate and Prosecutor, are rolled up into one and delegated to the Son.

JUDGE

"Judge" is usually thought to be the one who decides innocence or guilt ("judges"), but a little consideration of the earthly pattern will show that is NOT the job of the judge, but is the job of the JURY. Likewise, in heavenly judgments. The judge's main duty is to assure that the trial is fair and proceeds efficiently. The JURY typically decides innocence or guilt. Likewise in the heavenly judgments. So, who is the judge? Not the Father. The Son is the judge.

For the Father judgeth no man, but hath committed all judgment unto the Son: John 5:22

For as the Father hath life in himself; so hath he given to the Son to have life in himself; And hath given him authority to execute judgment also, because he is the Son of man. John 5:26-27

He that rejecteth me, and receiveth not my words, hath one that judgeth him: the word that I have spoken, the same shall judge him in the last day. John 12:48

And he [Yahushua] commanded us to preach unto the people, and to testify that it is he which was ordained of יהוה [Yahweh] to be the Judge of quick and dead. Acts 10:42

Because he [Yahweh] hath appointed a day, in the which he will judge the world in righteousness by that man whom he hath ordained [the Messiah]; whereof he hath given assurance unto all men, in that he hath raised him from the dead. Acts 17:31

For we must all appear before the judgment seat of the Messiah; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad. 2 Corinthians 5:10

Henceforth there is laid up for me a crown of righteousness, which Yahushua [Jesus, the Messiah], the righteous judge, shall give me at that day: and not to me only, but unto all them also that love his appearing. 2 Timothy 4:8

ADVOCATE

An advocate acts as a defense attorney or lawyer, helping the defendant prove innocence or negotiate a lighter sentence. The Son is our advocate.

My little children, these things I write to you, so that you may not sin. And if anyone sins, we have an Advocate with the Father, Yahushua the Messiah the righteous. 1 John 2:1

For there is one Elohim, and one mediator between Elohim and men, the man Yahushua the Messiah; 1 Timothy 2:5

For the Messiah is not entered into the holy places made with hands, which are the figures of the true; but into heaven itself, now to appear in the presence of יהוה for us: Hebrews 9:24

All we like sheep have gone astray; we have turned every one to his own way; and יהוה hath laid on him the iniquity of us all. Isaiah 53:6

Whosoever therefore shall confess me before men, him will I confess also before my Father which is in heaven. Matthew 10:32

PROSECUTOR

In trials on earth, the "prosecutor" or "prosecuting attorney" presents evidence for the government and tries to get the defendant convicted. This is an office very similar to that of Satan, our accuser.

And the great dragon was cast out, that old serpent, called the Devil, and Satan, which deceiveth the whole world: he was cast out into the earth, and his angels were cast out with him. And I heard a loud voice saying in heaven, Now is come salvation, and strength, and the kingdom of our Elohim, and the power of his Messiah: for the accuser of our brethren is cast down, which accused them before our Elohim day and night. Revelation 12:9-10

This is NOT the work of our Messiah as prosecutor in the heavenly courts.

Do not think that I will accuse you to the Father... John 5:45

Jesus [Yahushua] will work to convict, but not to accuse. There is a (seemingly) subtle but significant difference. Human prosecutors are primarily working to increase their conviction rate for political advancement and "putting away" (incarcerating) the defendant (guilty and innocent). In contrast, the purpose of the King / judge / prosecutor is convicting and converting the defendant's spirit by FIRE. This fire is NOT a form of torture or inquisition meant to force a confession but is His Word, speaking Truth in Love, meant to open the heart and purify the soul (see Purification by Fire).

This prosecutor uses FIRE to convict, convert and purify. This fire is His word. His Word is the Lake of Fire.

For by fire and by his sword will Yahweh plead with all flesh: and the slain of Yahweh shall be many. Isaiah 66:16

Is not my WORD like as a FIRE? saith Yahweh; and like a hammer that breaketh the rock in pieces? Jeremiah 23:29

Then flew one of the seraphims unto me, having a live coal in his hand, which he had taken with the tongs from off the altar: And he laid it upon my mouth, and said, Lo, this hath touched thy lips; and thine iniquity is taken away, and thy sin purged. Isaiah 6:6,7

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

See:
The Lake of Fire
Purgatory and the Lake of Fire
Purification by Fire

His mouth will reveal and declare all.