Is saying "I don't want to trouble you, by God" considered a lie or a false oath when refusing an offer of help out of fear of theft?

The mere statement "I do not want to trouble you" is not considered a lie, even if the intention is to protect one's belongings and avoid theft. Lying is intentionally informing about something contrary to its true state. Following the sentence with "by Allah" is considered a 'laghw al-yamin' (unintended oath) for which there is no expiation, because it is something that passes over the tongue without intention, as confirmed by Allah's saying: "Allah will not impose blame upon you for what is unintentional in your oaths, but He will impose blame upon you for what your hearts have earned [of intention]." One should not preoccupy themselves with such matters, which may lead to obsessive thoughts.