Christ is both Advocate and Judge in a different sense--or time, as the case may be. He is now our Advocate. After the investigative judgment is finished, He will then be the Judge for the final judgment.
That's what I said, but I said "perhaps" because the Bible says both that "the Father judges no man, but has committed all judgment to the Son" (John 5:22) and that "And I will not blot out his name out of the Book of Life, but I will confess his name before My Father and before His angels" (Rev. 3:5).
But in fact, in ancient Israel there were no prosecutors or defense attorneys; accuser and accused argued their own cases. And, by deciding in its favor, the judge himself was defending the right party.
So I was favorably inclined to Arnold's position, and now I think I've found a passage which seems to confirm its correctness:
Can you, dear youth, look forward with joyful hope and expectation to the time when the Lord, your righteous Judge, shall confess your name before the Father and before the holy angels? {OHC 368.2}
Besides this, there is the classical passage:
And Christ has been made our Judge. The Father is not the Judge. The angels are not. He who took humanity upon Himself, and in this world lived a perfect life, is to judge us. He only can be our Judge. Will you remember this, brethren? Will you remember it, ministers? Will you remember it, fathers and mothers? Christ took humanity that He might be our Judge. CCh, 259