An aboleth eye seems to glow with an unnatural hatred that can pass to the keeper of it.

While holding the eye, you can use a bonus action to gain the sight of an aboleth for 1 minute, causing the eye to glow a bright alien green as it fuses with the small portion of your body that it is nearest too. This causes you to gain darkvision out of a range of 45 feet (if you already have darkvision, this adds to it) and you can sense the presence of and can hear telepathy up to 15 feet away from you.