What is the ruling on swearing the most solemn of oaths?

An oath is binding if it is sworn by one of the names of Allah Almighty or by one of His attributes. It is permissible to make an oath more emphatic by adding names and attributes, such as saying: "By Allah, the Most Merciful, and by Him besides whom there is no god, the Ever-Living, the Sustainer," based on the hadith (definition) of Abu Hurairah (may Allah be pleased with him). If he does not repeat the words of the oath but says: "I swear by the most emphatic of oaths," then his oath is binding. An oath is made more emphatic for matters of great importance, such as large sums of money, qisas (retribution), and theft, and this is left to the discretion of the judge. It is not made emphatic for simple matters.