This lion was once the mount of the bodhisattva Monju (Skt. Mañjuśrī); one sees the base of the deity’s pedestal on the saddle. There are very few examples of such lions with closed mouths who look straight out. The statue is dated to the eleventh century on the basis of such features as its large, round bulging eyes, its raised ears at the top of its head, and its broad and puffed chest. 
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This lion was once the mount of the bodhisattva Monju (Skt. Mañjuśrī); one sees the base of the deity’s pedestal on the saddle. There are very few examples of such lions with closed mouths who look straight out. The statue is dated to the eleventh century on the basis of such features as its large, round bulging eyes, its raised ears at the top of its head, and its broad and puffed chest.
 
IWAI TomojiEnglish by Mary Lewine 
Buddhist Art Paradise: Jewels of the Nara National Museum. Nara National Museum, 2021.7, p.342, no.109. 

This lion was originally employed as the animal pedestal for a statue of Monju Bosatsu (Skt. Mañjuśrī). It was said to be come from Onjō-ji Temple in Shiga Prefecture. The body was painted with blue, the mane was painted with green and the belly was painted with red. The waist was interpreted in a very high, exaggerated position, however muscles, nails and the framework were realistically expressed.
 
Shigeki Iwata 
Masterworks from the Nara Buddhist Sculpture Hall at the Nara National Museum. Nara National Museum, 2010, p.138, no.151. 

This statue of a lion was originally kept in Onjō-ji temple in Shiga prefecture. There are holes in its back where a lotus seat and a shikinasu sheet used to be attached. Originally, a statue of Monju-bosatsu (Mañjuśrī) was riding on the back of this lion. It is conceivable that Monju-bosatsu on the lion's back was accompanied by attendants, such as Zenzai-dōji (Sudhana Śreṣṭhidāraka), Udennō (King Udayana), Butsudahari Sanzō (Buddhapāli Tri-piṭaka) and Saishō-rōjin. This type of Monju with four accompanying attendants was worshipped as "Tokai Monju" (Mañjuśrī who is crossing the ocean) during the days when it was made.
The material of this statue is thought to be hinoki (Japanese cypress). The whole body of this lion is carved from a single block of wood. The color on the surface has not come off nor faded. The lion is holding its head upright and is looking forward instead of turning its head to the side. The head is relatively small. Considering of these aspects, by and large, it is a lion made in a classic style. 
Masterpieces of Nara National Museum. Nara National Museum, 1993, p.25, no.13.