Question: Some say that [1] Green Tārā (绿度母), [2] Mother Mary (圣母玛利亚) and [3] Māzǔ (妈祖) are aspects of Contemplator Of The World’s Sounds Bodhisattva (观世音菩萨: Guānshìyīn Púsà). Is this so?
Answer: Just because the physical cultural depictions of the above look somewhat similar does not mean they are all totally aligned in essence. However, as depicted in Vajrayāna (金刚乘) teachings (i.e. Tibetan Buddhism: 藏传佛教), the [1] first listed represents Guānshìyīn Púsà’s manifestation of active compassion. The other two listed are not connected to her, while having connections to other concerns.
[2] The second listed has no teaching connecting to core Buddhist teachings directly, while connecting to those of a very different central subject of faith, that Buddhists do not subscribe to — the concept of a ‘creator diety’, (who ‘made’ everything, including darkness). Guānshìyīn Púsà’s teacher is Āmítuófó (阿弥陀佛: Amitābha Buddha), who is the creator of the Western Pure Land Of Ultimate Bliss (西方极乐世界), (a world of bright light).
[3] The third listed was worshipped by many fishermen (and other seafarers) originally. As Guānshìyīn Púsà has all-encompassing Great Compassion (大悲) for all sentient beings, including both human beings and all sea animals big and small, it is not so that she will protect only the fishing humans, versus the many fish continually being caught and killed by those humans. In fact, Guānshìyīn Púsà will discourage fishing, which is to ‘make a living through killing.’
To respect different faiths, we should not conflate them superficially to be one and the same, as they are exactly different faiths because they have different teachings and concerns. Of course, there might be some similarities, which form the common ground for interfaith harmony. However, they are usually not perfectly aligned in one-to-one ways. The true way to respect various faiths is to see and acknowledge both their similarities and differences, just as they are.