What are the conditions for a just witness in marriage according to Imam Al-Shafi'i?

The conditions for a witness in marriage are: Islam, sanity, masculinity, puberty, and justice (adalah). This is the view of the majority of scholars. Their evidence is the hadith: "There is no marriage except with a guardian (wali) and two just witnesses." Justice (adalah), according to the Shafi'is, requires five conditions: abstaining from major sins, not persisting in minor sins, having a sound inner character, being trustworthy when angry, and maintaining decorum (muru'ah).