The new inkings appear to be a crucifix in the centre of his chest, and a sculpture.
A shivering David captioned the video "It's too damn cold" as he swam in the icy water.
The new tattoos join David's ever-growing collection of body art.
He's honoured his children and his wife, Victoria, in his tattoos in the past.
When his daughter Harper was born in 2011, David had his name etched into the back of his neck.
And he added a tiny black heart tattoo onto his ear earlier this year - which some say is a tribute to Victoria.