When people saw bodies of Ibraheem, his son Ishaq and his son Yaqub (peace be upon them).
Ibn Kathir said:
وفيها: ظهر قبر إبراهيم الخليل عليه السلام وقبر ولديه إسحاق ويعقوب، وشاهد ذلك الناس، ولم تبلَ أجسادهم، وعندهم قناديل من ذهب وفضة، ذكر ذلك ابن الخازن في (تاريخه)، وأطال نقله من (المنتظم) لابن الجوزي، والله أعلم
And in this year: the grave of Ibrahim Al-Khalil, peace be upon him appeared and the grave of his sons, Ishaq and (grandson) Yaqub (May peace be upon them). The people witnessed that, and their bodies were fine, and lamps of gold and silver were near them. Ibn al Khazin mentioned this in his tareekh, And he transmitted it at length from (Al-Muntazim) of Ibn Al-Jawzi, and Allah knows best.
(al Bidaya wal Nihaya the year 513 h)
Umar bin al Khattab rightly said about the body of Danial aleh salam.
إن هذا نبي من الأنبياء والنار لا تأكل الأنبياء , والأرض لا تأكل الأنبياء
Indeed this is a Prophet from the Prophets. The fire does not eat the Prophets, nor does the earth.
[Musannaf Ibn Abi Shaybah (33819)]