Expressing Regret Over Death

Is it permissible to say at a eulogy or during comforting mourners, "I regret your death, my brother"?

It is forbidden to say "I regret his death," as it sounds like complaining about the ways of the Almighty. However, it is permissible to say "I regret for you."

Sefer Maharil (Minhagim), Likutim, letter 68: "Once a great man, the son of a duke from Heidelberg, who loved Israel, died, and someone said before Rabbi Maharil Segal, 'I regret his death.' And the Rabbi said, 'Even if he were a righteous Jew and a great Torah scholar, one should not say so, as it appears to complain about the measure of judgment, only say that his death caused great harm.'" In the book of the prophet Samuel II, chapter 1, verse 26, we find that David said about Jonathan: "I am distressed for you, my brother Jonathan; you were very dear to me." It should be understood that "I regret for you" speaks of his absence, which is felt, but when saying "I regret his death," it speaks of the measure of judgment.