St Guthlac, the Mercian soldier-turned-hermit who founded the abbey of Crowland in Lincolnshire, arrived at his marshy, devil-haunted hermitage on St Bartholomew's Day, 24th August, 699 AD. Thereafter he chose St Bartholomew as his patron, and said that the apostle defended him from the demons who were constantly besieging his Fenland hideaway. Bartholomew even gave him a whip to beat off the demons; a fact apparently long remembered at Fishtoft in Lincolnshire.
(it seems that Bartholomew is thought to be the same person as Nathaniel from this great story, by the way)
And here's a repeat of something I posted a few months ago in relation to Crowland and St Bartholomew:
From the Chronicle of Crowland Abbey, Lincolnshire, this is a notable cost-cutting initiative by Abbot John Wisbech, who died in 1476:
"He it was who first wisely abolished that ancient or rather that corrupt custom of giving knives to every visitor on St Bartholomew’s day. By this both abbot and convent rejoice in being free for ever from heavy and needless expenses."
St Bartholomew, who was one of Crowland's dedicatory saints, suffered martyrdom by being flayed alive, and so one of his attributes is a knife. I guess people were given them as souvenirs? Sounds like it would get pretty expensive - and a bit of a health and safety issue too.