'Burnt offering' in the Bible

Then it shall be, that whatsoever comes forth of the doors of my house to meet me, when I return in peace from the children of Ammon, shall surely be the LORD'S, and I will offer it up for a burnt offering.

And the angel of the LORD said unto Manoah, Though you detain me, I will not eat of your food: and if you will offer a burnt offering, you must offer it unto the LORD. For Manoah knew not that he was an angel of the LORD.

But his wife said unto him, If the LORD were pleased to kill us, he would not have received a burnt offering and a grain offering at our hands, neither would he have showed us all these things, nor would at this time have told us such things as these.