What is the legal basis for considering the state of heirship when judging the validity of a declaration of debt?

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The opinion that judges the state at the time of death, like a bequest, is attributed to Sufyan al-Thawri and Al-Shafi'i, because it is a matter where the absence of inheritance is considered. However, the ruling that judges the state at the time the declaration was made is preferred because the matter is one where suspicion (*ittiham*) is considered, similar to testimony (*shahadah*). A declaration to a non-heir is established and valid because it originated from someone qualified and free from suspicion, whereas a declaration to an heir is void due to the inherent suspicion.