Muse not that by, &c. l. 7. a Lay Mans Genius: i.e. his Guardian Angel. The 'Lay Man' is opposed to the 'Poet'. Donne is very familiar with the Catholic doctrine of Guardian Angels and recurs to it repeatedly. Compare Shakespeare, Macbeth, III. i. 55.
l. 11. Wright then. The version of this poem in W is probably made from Donne's autograph. One of his characteristic spellings is 'wright' for 'write'. The Losely Manuscripts (ed. Kempe, 1836), in which some of Donne's letters are printed from the originals, show this spelling on every page. It is perhaps worth noting that the irregular past participle similarly spelt, i.e. 'wrought', has occasionally misled editors by its identity of form with the past participle of the verb 'work', which has 'gh' legitimately. Thus Mr. Beeching (A Selection from the Poetry of Samuel Daniel and Michael Drayton, 1899) prints:
Read in my face a volume of despairs,
The wailing Iliads of my tragic woe,
Drawn with my blood, and painted with my cares,
Wrought by her hand that I have honoured so.
Here 'wrought' should be 'wrote', used, as frequently, for 'written'. In Professor Saintsbury's Patrick Carey (Caroline Poets, II.) we read:
Who writ this song would little care
Although at the end his name were wrought.
i.e. 'wrote'.