Law: source of obligation

Article 1158 of the Civil Code of the Philippines provides:
Art. 1158. Obligations derived from law are not presumed. Only those expressly determined in this Code or in special laws are demandable, and shall be regulated by the precepts of the law which establishes them; and as to what has not been foreseen, by the provisions of this Book. (1090)
Law is one of the sources of obligation.[1] An obligation arises when there is an enforcement of law itself. Obligations arising from law is not presumed. Hence, only those that are expressly provided by the Civil Code or determined in special laws are demandable. An example of obligation arising from law is the obligation of the taxpayers to pay taxes in accordance with the tax statutes.[2] 

[1] Art. 1157, NCC.

[2] Rabuya, E. (2019). Obligations and Contracts.