In the past, a young Hiruzen, who was the master of the future Sannins, invoked Enma to show the Summoning Jutsu to a young Jiraiya and he could learn to use it.
Enma and the 3rd HokageEnma along with Hiruzen as a young man.
Enma participated with his summoner, Hiruzen, in the attack of the Nine-Tailed Fox, where they were taking that beast out of the village. Later, the two are seen near the Kushina barrier watching the Bijū sealing moment