Antonyms for the phrase "threw light upon" may include phrases like "obscured the truth," "muddled the situation," or "cast a shadow on." Other antonyms might include words such as "obfuscate," "bewilder," or "confuse." These words imply a deliberate attempt to obscure or hide the truth, rather than to reveal it. When someone throws light upon a subject, they illuminate it and provide clarity. Conversely, when someone obscures the truth or muddles the situation, they intentionally or unintentionally make it more difficult to understand. Therefore, it is important to use precise and accurate language to convey the intended meaning in any communication.