In possession of one's faculties and Of sound mind

Of sound mind and in possession of one's faculties are semantically related. In some cases you can use "Of sound mind" instead an adjective phrase "In possession of one's faculties".

Of sound mind adjective - Of sound mind, memory, and understanding; in law, competent to go to trial.

In possession of one's faculties and of sound mind are semantically related. You can use "In possession of one's faculties" instead an adjective phrase "Of sound mind".