Silsilat al-Ahadith al-Sahihah

A woman from the tribe of Juhaina, Sayyida Qateela bint Saifi (may Allah be pleased with her), says: A Jewish scholar came to the Prophet (peace and blessings of Allah be upon him) and said: "You people commit shirk, because you say: 'Whatever Allah wills and you will,' and you swear by the Ka'bah." The Messenger of Allah (peace and blessings of Allah be upon him), upon hearing this, said: "You should say: 'Whatever Allah wills and then you will,' and when swearing, say: 'By the Lord of the Ka'bah.'"