The essence of the meaning revolves around His saying 'alone.' This means that when Allah is mentioned exclusively and their deities are not mentioned with Him, they feel disgusted. This means they turn away and become withdrawn. And when those besides Him are mentioned, whether Allah is mentioned with them or not, they rejoice, due to their attachment to them and their forgetting of Allah's right, which is more important to them. It is said that when it is said 'there is no deity except Allah alone, without partner,' they turn away, because it negates their deities. It is also said that they were pleased with what the tongue of the Messenger of Allah, blessings and peace be upon him, previously mentioned regarding their deities when he recited 'and the star' at the Kaaba, and they prostrated with him out of joy. Indeed, the feelings of joy and disgust are opposites, as each is an extreme in its own right. Joy is when the heart is filled with happiness to the extent that the face brightens and becomes radiant. Disgust is when one is filled with sorrow and anger to the extent that withdrawal appears on the surface of the face. If you ask: What is the cause of 'when it is mentioned'? I say: The cause of 'when' is the surprise, meaning the time of mentioning those besides Him. They were surprised at the time of joy.