Musnad Ahmad 2:258

Sufyan narrated to us, from Ayyub, from Ibn Sirin, who heard it from Abu al-Ajfa’: I heard Umar saying: Do not exaggerate the dowries of women, for if it were an honor in this world or piety in the Hereafter, the Prophet (peace and blessings of Allah be upon him) would have been more entitled to it than you. He did not marry off any of his daughters, nor did he marry any of his wives, for more than twelve ounces. And there is another thing you say in your military expeditions: "So-and-so was killed as a martyr," or "So-and-so died as a martyr," while he may have loaded the rear of his mount or packed his riding beast with gold and silver, seeking trade. So do not say that, but say as Muhammad (peace and blessings of Allah be upon him) said: "Whoever is killed in the way of Allah is in Paradise."