Sisyphus punishment, to roll a rock on top of a moutain forever, is said to have been given because of his trickery with Thanatos.
However, it seems that the reason behind this punishment was not explicitely stated : French Wikipedia states on the subject this.
Toutefois, Homère ne faisait pas mention de la raison de ce châtiment. Certaines traditions le justifient par la réputation de brigand et de malfaiteur que Sisyphe avait acquise de son vivant.
However, Homer did not mention the reason of the punishment. Certain traditions justify it by [Sisyphus's] reputation of a criminal and wrongdoer that [he] has developed during his life.
So what was the reason behind the punishment? And what is the source behind the reason being the trickery with Thanatos, as explained in the English Wikipedia?