Sage or Salvia officinalis is a culinary, medicinal and ornamental “perennial, evergreen subshrub, with woody stems, grayish leaves, and blue to purplish flower,” notes Wikipedia.
This plant belongs to the family Lamiaceae, commonly referred as to the mint family and its leaves are also used to extract oil.
Finally, its other common names include garden, golden, kitchen, true, dalmatian, broadleaf, common, and culinary sage.
Is it safe for cats?
Yes. Sage is safe for cats. Therefore, if your kitty nibbles this herb leaves a little or eat cat-safe food with this aromatic culinary herb, you should not be worried as it is not poisonous or toxic.
However, do not allow your kitty to eat a lot of sage or any other herb, vegetable or plant material as they can cause stomach upsets, diarrhea, vomiting, abdominal pain and so on. This happens because feline’s digestive systems are more adapted to process meats and only a small amount of carbohydrates and plant materials.
Add to your cat’s food or homemade snacks only a small amount of its chopped leaves or a pinch of dried grounded leaves. Do not give them a lot since it has little nutritional benefits since kitties cannot digest it well,
Does it have any benefits? Yes. Your kitties can benefit from its fiber that can help in digestion as well as its astringent, antiseptic, antimicrobial and antispasmodic properties.
Is burning sage safe for cats
Smudging or burning sage especially white sage is part of ancient native America cultural ritual but also practiced in many cultures across the world.
There are many benefits associated with smudging including boosting cognition, mood and energy levels, soothing stress, improving sleep, oust any negative energies, relieve some conditions, and so on.
While there are no studies to show if smudging benefits kitties, smudging is not dangerous to cats besides the possible effects of smoke.
The smoke may irritate their respiratory system. This is more commonly noted in those that have asthma, bronchitis or any other pre-existing respiratory issues.
Sneezing, watery eyes, and other respiratory problem symptoms may indicate that smudging is affecting your kitties.
In such a case, open windows, ensure your house is well ventilated or do it in a room where your felines cannot access.
While this plant’s fresh leaves or dried ones are safe because they have a low concentration of sage essential oil, the extracted oil is not safe to pets since it has ketones 
Bee, Sacred, white sage or Salvia apiana is a different species and not the same as Salvia officinalis. Its seeds and leaves are edible, its roots are used in making tea and its leaves are commonly used in smudging.
White sage is safe for cats in small amounts. Large amounts may cause stomach upsets.
Sage is not toxic or poisonous to cats. It is normal for cats to nibble its leaves a little bit. Some will not like it owing to the strong taste and aroma.