A more thorough explanation:

An institute can refer to:

1. A legal treatise or commentary, such as Coke's Institutes in four volumes (published in 1628).
2. An elementary treatise on Roman law in four books. This treatise is one of the four component parts of the Corpus Juris Civilis.
3. An elementary treatise written by the Roman jurist Gaius. The Institutes, written in the second century A.D., served as a foundation for the Institutes of Justinian.
4. A paraphrase of Justinian's Institutes written in Greek by Theophilus, a law professor at Constantinople who helped prepare the Institutes of Justinian.
5. A person named in a will as heir, but under directions to pass the estate on to some other specified person (called the substitute).
6. An organization devoted to the study and improvement of the law, such as the American Law Institute.

• John studied Coke's Institutes in law school to gain a better understanding of legal commentary.
• The Institutes of Justinian is an important text in the study of Roman law.
• Gaius' Institutes served as a foundation for the development of Roman law.
• The Paraphrase of Theophilus helped prepare the Institutes of Justinian.
• Tom was named as an institute in his grandfather's will, but was directed to pass the estate on to his cousin.
• The American Law Institute is an organization that works to improve the law through research and education.

These examples illustrate the different meanings of the term "institute" in the legal context, including legal commentary, foundational texts, wills, and organizations devoted to the study and improvement of the law.