Silsilat al-Ahadith al-Sahihah

It is narrated from Sayyiduna Abu Hurairah (may Allah be pleased with him), he says that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever seeks the world, he harms his Hereafter, and whoever seeks the Hereafter, he harms his world. So let the loss of the perishable (world) be for the sake of the everlasting (life)."