The Traditional Thai Murals that are found in the temple resembles much of those that can be found in Thailand today. Traditional Thai art primarily consists of Buddhist art with influences from Thai folklore and Hinduism; Thai sculptures most often depict images of the Buddha and other characters from Buddhist and Hindu mythology. From the 1st to the 7th centuries, art in Thailand was influenced by direct contact with Indian traders and the expansion of the Mon Kingdom, leading to the creation of Hindu and Buddhist art inspired by Indian traditions. Paintings of Thai Buddha from different periods have a number of distinctive styles, and contemporary Thai art often combines traditional Thai elements with modern techniques.  The artwork that is found at the temple are from the Mahanipata Jakata
Mahanipata Jataka (mahānipāta jātaka), (Ten Great Birth Stories of the Buddha), are stories from the longer Jataka collection. These tales are the ten final lives of the Bodhisatta, the future Gotama Buddha. Each Jataka story illustrates one of the 10 virtues to be fully developed to become a Buddha. The virtues are renunciation, vigour, compassion, fortitude, insight, morality, patience, equanimity, veracity and generosity.
After the last story, Vessantara, the Bodhisatta appears in the Brahma realm before his next form as a human being.
With reference to https://courses.lumenlearning.com/boundless-arthistory/chapter/thai-art/
wall mural A
wall mural B
Wall Mural C
Wall mural D
Information on Wall Murals with reference to
Theravada Buddhist tradition tells a story of a monk who travels to hell on his way to pay homage to the Buddha's hair relic kept in the Chulamani Stupa and to meet with the future Buddha.
This venerable is known as Phra Malai. In the temple's new mural he is flying above all the suffering beings. Different unwholesome karma results in Lord Yama assigning beings to the different woeful Realms; the tall hungry Ghost on the right has a pinhole-sized mouth. The killing of animals results in ghosts with the head of the animal that they slaughtered.
Hitler, Pol Pot and Ossama bin Laden join the crowd. The beings plead with Phra Malai to have their living relatives transferred merit to them.
On the far left are sexual offenders forced to climb the thorny "ngiu" tree while a butcher has an axe embedded in his skull.
Temple door drawings by Dr. Irving
Dr. Irving Chan Johnson is an anthropologist and traditional Thai illustrator. He received his Ph.D. in Anthropology from Harvard University in 2004. He has been practising Thai art since he was a child and currently teaches traditional Thai painting at the National University of Singapore.
He is currently a mural painter at Wat Uttamayanmuni, a Thai Buddhist temple in Singapore. Irving's art work blends traditional Thai techniques and aesthetics with contemporary images to create unique works that embody the past in the present. The result challenges viewers to simultaneously engage with present-day society in the frame of a classical Thai genre.
Most recently, Irving was commissioned by the British Library to create a special piece as a part of an exhibition on Buddhist art. Irving has also designed a temple gateway in Malaysia, paintings and traditional temple logos. He has conducted lectures and workshops on Thai art in Singapore and the United States.