The antonyms for the word "hast doubts" are confidence, certainty, and assurance. When one is confident, they have faith in their abilities or in someone else's abilities. They don't doubt their actions, decisions, or judgments. When one is certain, they have no doubts or hesitations about something. When one has assurance, they have a sense of safety and protection, which means they're entirely sure about something. Such antonyms help in understanding the positive aspects of life and, in turn, promote positivity and self-belief. Instead of doubting, one must learn to have confidence, certainty, and assurance in their abilities and decisions.