Opinio juris is a fundamental element of customary international law. It represents the belief held by states that a certain practice is carried out of a sense of legal obligation, not merely out of habit or convenience. This belief helps distinguish legally binding customs from mere general practices, preventing unwanted or casual practices from being recognized as law.
Statement 1 is correct because opinio juris ensures only those practices carried out with a sense of legal duty become customary law.
Statement 2 correctly defines opinio juris as the belief that an action is performed because it is legally obligatory.
Therefore, both statements are correct.