Since the martyr is alive and eternal, is it permissible for us to swear by his life?

It is not permissible to swear by a created being, such as the life of martyrs or others, because Allah the Almighty forbade swearing by fathers or any other created being, and commanded to swear by Allah or to remain silent. Whoever swears by other than Allah has committed shirk (associating partners with Allah). A martyr is alive, but it is not permissible to swear by his life or his being, for swearing by other than the names and attributes of Allah is forbidden.