George E. Pennington was educated in Kendal, England, and came to South Africa in 1883. On 30 January 1895 he married Anne S. Mission, with whom he had five sons. He served as senior chaplain to the Natal forces during the Anglo-Boer War (1899-1902) and at some stage received the "Volunteer Decoration, Holy Orders, English Church". By 1918 he had attained the rank of archdeacon and in 1921 published a pamphlet, Common provincial fund: Proposed new method of assessing the Diocese. Around that time he resided in Greytown, KwaZulu-Natal, but from 1925 to 1930 he held the positions archdeacon of Pietermaritzburg and vicar-general of Natal.
Pennington's recreational activities included various sports, fishing, and collecting butterflies and birds' eggs. His book Trout fishing for South African boys was published in Pietermaritzburg in 1911. He also collected land snails in KwaZulu-Natal. These he sent to H.C. Burnup*, who named the species Gulella penningtoni (Pennington's hunter snail) after him in 1925. Pennington had collected the original specimens of this species, which is known from only a few localities along the KwaZulu-Natal north coast and southern Zululand. In 1916/7 he became a foundation member of the South African Biological Society and by 1920 had been elected an honorary member.