The phrase "hadst no doubt" is an archaic form of English meaning "you had no doubt." The spelling may seem strange, as it includes both "d" and "t" at the end of "hadst." This is because "hadst" is a contraction of "had" and "st," which means "did have." The "t" comes from the archaic second person singular past tense marker "st." The pronunciation is /hædst noʊ daʊt/, with stress on the first syllable of "hadst."