All moneys raised by taxation in the towns and cities for the support of public schools, and all moneys which may be appropriated by the commonwealth for the support of common schools shall be applied to, and expended in, no other schools than those which are conducted according to law, under the order and superintendence of the authorities of the town or city in which the money is expended; and no grant, appropriation or use of public money or property or loan of public credit shall be made or authorized by the commonwealth or any political division thereof for the purpose of founding, maintaining or aiding any other school or institution of learning, whether under public control or otherwise, wherein any denominational doctrine is inculcated, or any other school, or any college, infirmary, hospital, institution, or educational, charitable or religious undertaking which is not publicly owned and under the exclusive control, order and superintendence of public officers or public agents authorized by the commonwealth or federal authority or both, except that appropriations may be made for the maintenance and support of the Soldiers’ Home in Massachusetts and for free public libraries in any city or town, and to carry out legal obligations, if any, already entered into; and no such grant, appropriation or use of public money or property or loan of public credit shall be made or authorized for the purpose of founding, maintaining or aiding any church, religious denomination or society.]