In around 1843, based in Sibsagar, he began translating the New Testament into Assamese or "Amar Trankôrta Yisu Khristôr Nôtun Niyôm" () which he published in 1848. In 1854, he published another book titled meaning roughly "Jesus Christ and his Holy Messages". He also translated prayers alongside his other missionary colleagues. His work "Grammatical Notices of the Assamese Language" was published by the American Baptist Mission Press in 1848. In 1846, with his colleague Oliver Cutter, he published "Orunodoi" (), the first Assamese periodical. He also published works of contemporary and historical Assamese scholars, to name a few "Ôxôm Burônzi" ("History of Assam", ) by Kashinath Phukan in 1844, "Kitabôt Mônzôri" ("Mathematics", in Assamese verse, ) in two parts, "Lilawôti" and "Pôdgônit" by Bakul Kayastha in 1845, and "Sutiya Burônzi" () in 1850, as well as others. In Assam, Brown is considered to be a pioneer and champion of the native language and literature.