Opinio juris, a cornerstone of customary international law, signifies a state's conviction that a particular practice is undertaken due to a sense of legal obligation, rather than mere habit or expediency. This conviction differentiates legally binding customs from general practices, thereby precluding casual or unsolicited practices from being recognized as law.
Statement 1 is accurate as opinio juris mandates that only practices executed with a perception of legal duty can evolve into customary law.
Statement 2 accurately defines opinio juris as the belief that an action is performed due to its legal indispensability.
Consequently, both statements are accurate.