The work was bought by Father Jamie MacLeod from an antiques shop in Cheshire 12 years ago for just £400.The painting was identified after show presenter Fiona Bruce saw it and thought it might be genuine.Father MacLeod said he would be sad to part with the portrait but it had been a "blessing" to own it.'Excellent use'Bruce asked expert Philip Mould, with whom she was making a programme about the artist, to look at the painting.After a lengthy restoration process the painting was verified by Dr Christopher Brown, one of the world's leading authorities on Van Dyck.Father MacLeod, who runs a retreat in the Peak District, said he was "not being greedy" by selling the painting."It has been a blessing to own this magnificent portrait which has given me great pleasure over the years," he said."I will be sad to part with it, though the proceeds will be put to excellent use going towards the acquisition of new church bells for Whaley Hall Ecumenical Retreat House in Derbyshire to commemorate the centenary of the end of the First World War in 2018."The retreat house, "is about cohesion, ecumenism and working with people that are sometimes on the edge of society," he told BBC Radio 4's Today programme.The painting is believed to be a sketch for a work called The Magistrates of Brussels, which hung in the city's town hall until it was destroyed by a French attack in 1695.'Great importance'Christie's specialist Freddie de Rougemont said: "We are delighted to present this beautifully observed head study by Sir Anthony van Dyck for sale, particularly after its exciting re-discovery on the Antiques Roadshow."The picture is of great importance as it provides a fascinating insight into Van Dyck's working method and also constitutes a significant surviving document for the artist's lost group portrait of The Magistrates of Brussels."The portrait will be on public display at Christie's New York from Saturday until Tuesday, then in London from 5 to 8 July when it will be sold at Christie's Old Master and British Paintings auction.Van Dyck was born in modern-day Belgium and came to work in England in 1632 at the invitation of King Charles I.(BBC)Bakudaily.az