1. Nāga Sutta

Once, when the Buddha was seated under the Ajapāla Banyan tree, soon after his Enlightenment, Māra assumed the form of a fearsome elephant and tried to frighten him. But the Buddha recognised Mara and sent him away discomfited. S. i.103f.

2. Nāga Sutta

A certain novice was in the habit of upending too much time in clansmen's houses. When warned against this, he answered that he could not understand how he was to blame when he saw many senior monks acting in the same way.

He was reported to the Buddha, who related the story of an elephant who dwelt by a great lake. He plunged into the lake, pulled up lotus stalks, cleaned them and then, by eating them, gained strength and beauty. But when the baby elephants tried to follow his example, they could not clean the stalks, and eating them with mud and dirt, they grew sick, some of them even dying (S.ii.268).

3. Nāga Sutta

Snakes which dwell in the Himālaya, when grown and strong, find their way into the sea, where they grow even greater. Even so do monks, who develop the Noble Eightfold Path (S.v.47).

4. Nāga Sutta

An elephant, to be fit for the royal stalls, should have four qualities: he should be a good listener (sotā), a good slayer (hantā), full of patience (khantā), and a good goer (gantā). A monk should have the corresponding qualities in order to be fit for the respect and gifts of the world. A.ii.116.

5. Nāga Sutta

The Buddha goes to the bathing place near the Migāramātupāsāda with Ananda, bathes there, and, while drying his limbs, sees Pasenadi's elephant, Seta, coming out of the bathing place, attended by great ceremony. People, seeing him, express their wonder and admiration of the noble animal.

Udāyī (Kāludāyī, says the Commentary, AA.ii.669), who is near by, asks the Buddha if it is only the elephant whom people praise for his bulk or do they praise other bulky things as well? They do, says the Buddha., praise all huge things -  horses, bulls, snakes, brew, and big men, calling them Nāgas, but really, the best Nāga is he who commits no enormity in word or thought (āgun na karoti, tamnāgo). Thereupon Udāyi breaks forth into song, praising the Buddha's teaching, comparing the Buddha to an elephant, each limb representing a different virtue (A.iii.345).

This sutta is also called Nāgopama Sutta. ThagA.ii.7.

6. Nāga Sutta

Sometimes it happens that a forest dwelling elephant gets bored with the company of his fellows, his women folk and the young elephants who get in his way and interfere with his freedom. Thereupon he breaks away from them and retires into solitude. So should the monk, wearied of the haunts of men, resort to loneliness and there rid himself of the Āsavas. A.iv.435.

Nāga Vagga

The twenty third chapter of the Dhammapada.

Nāga Samyutta

The nineteenth section of the Samyutta Nikāya. S. iii.240-6.