Is it bad to swear on lives then do the opposite?

Yes, swearing on lives and then acting contrary to that commitment can be seen as deceitful and dishonorable. It undermines trust and can damage relationships, as people rely on the integrity of such promises. Such actions may also reflect poorly on one's character, suggesting a lack of respect for the seriousness of the vow made. Ultimately, it can lead to significant consequences for both personal and professional interactions.