When was the word 'being' first used to refer to a human being or sentient being?

Solution 1:

The Online Etymology Dictionary may be right, but unfortunately it gives no citations in support of its claims. Being does indeed first appear as a noun in the fourteenth century but in the sense ‘a living creature, either corporeal or spiritual; especially a human being, a person’, the OED's earliest citation is dated 1666:

If there were no Sensitive Beings, those Bodies that are now the Objects of our Senses, would be but dispositively, if I may so speak, endowed with Colours, Tasts, and the like.

Solution 2:

http://www.etymonline.com/index.php?term=being

... says early 14th century.

There are lots of such nouns; happening, turning, meeting, gathering, passing, clearing...

http://www.etymonline.com/index.php?term=human says the construct "human being" is attested by the 1690s.

Solution 3:

Here's a trio of early citations.

• 1625's The Booke of Honour: or Five Decades of Epistles of Honour by Francis Markham:

• 1629's Practique Theories by John Gaule

• 1630's A Discoverie of the Sect of the Banians by Henry Lord: