It might appear at first that Elijah is proposing a simultaneous contest. Such is not the case. Elijah once again seems to give the advantage to his opponents. He tells the prophets of Baal, You choose the bull, and you begin the contest.
This is not an act of generosity, nor is it the behaviour of a home team
host trying to be polite. It is part of the divine strategy to expose and humiliate Baal and his followers as completely as possible. By letting them choose the bull and start first, Elijah removes every excuse and ensures that the failure of Baal will be undeniable.
25 Elie dit aux prophètes de Baal: Choisissez pour vous l'un des taureaux, préparez-le les premiers, car vous êtes les plus nombreux, et invoquez le nom de votre dieu; mais ne mettez pas le feu.