Book of Jubilees 49:3

And this is the sign which the Lord gave them: Into every house on the lintels of which they saw the blood of a lamb of the first year, into (that) house they should not enter to slay, but should pass by (it), that all those should be saved that were in the house because the sign of the blood was on its lintels.

Background and history of Book of Jubilees, and issues with this book.

R. H. Charles, The Book of Jubilees, in The Apocrypha and Pseudepigrapha of the Old Testament, vol. 2 (Oxford: Clarendon Press, 1913). Public domain in the United States (published 1913). Charles died in 1931, so the book is in the public domain in the United Kingdom. The verse text is the Joshua Williams transcription at pseudepigrapha.com. Jubilees 1:8 and 1:9 are divided at the break in the 1902 Clarendon scan (archive.org bookofjubileesor00char), where verse 9 begins “For they will forget.” That scan also numbers the angel-of-the-presence sentence as 1:29. Editorial brackets in the translation are Charles’s.