The National Basilica is a sign of faith of Sri Lankans for it was built as a fulfillment of the vow made by the late Archbishop of Colombo Most Revd Dr. John Mary Masson at the feet of Blessed Virgin Mary at Tewatta. It was a great request made on behalf of the country for it was in need of protection and safety due to the 2 nd World War. Our Mother listened to the prayers of the people and our country was saved miraculously.

After the death of Archbishop Masson the responsibility of offering the vow was submitted to his successor Most Revd. Dr. Thomas Cardinal Cooray, the first Sri Lankan Archbishop as well as the first Cardinal of Sri Lanka. He took it on his shoulders and with the help of the faithful the vow was fulfilled by building the Basilica.