This is the famous graffiti in St Mary's Church, Ashwell, Hertfordshire. It records the great plague of 1348 and the storm of 1361 which blew down the spire of Norwich Cathedral on St Maur's day. The inscription says:

Pestile cia
MCT (er) x penta miseranda ferox violenta
(discessit pestis) superset plebs pessima testis in qevent(us) (erat) valid(us)
(h)oc anno mauris In orbe tonat MCCC LXI.

There was a plague
1000 three times 100, five times 10 a pitiable fierce violent (plague departed)
a wretched populace survives to witness
and in the end a mighty wind Maurus, thunders in this year of the world, 1361.