Is a person sinful if they say the word "amanah" (trust/custody) by mistake or out of habit, and what should they do in this case?

If the questioner, by saying “amanah” (trust/oath), meant to swear an oath, then it is not permissible, because there is a prohibition against swearing by amanah. Scholars have considered it a minor shirk. Whoever is accustomed to saying it should strive to abandon it and should say “La ilaha illa Allah” (There is no god but Allah) if he has sworn by it.