Taken from research from the Journal of Volcanology and Geothermal Research of Elsevier ;
Nicaragua’s conquest started only 30years after Christopher Columbus arrived to America in 1492. At that moment the Masaya and Momotombo volcanoes were erupting simultaneously. Some people believed that it was the Mouth of Hell, whereas others could greedily see in the lava a source of gold or silver. This fact led to many attempts trying to prove it.
During the 1772 eruption, the bishop of Granada, followed by numerous fellows, carried the image of the Christ of Nindiri in a procession and faced the coming lava flow in order to stop it. Oddly enough, the eruption did cease after that For this reason, since 1772, every 16th of March a big religious procession takes place in this region.
From the beginning of Nicaragua’s conquest, the Spaniards referred to the Masaya Volcano as “The Mouth of Hell” or simply “Masaya’s Hell” (Infierno de Masaya in Spanish).
This name was also following the tradition of the Aboriginal people who believed that the Masaya volcano was a god. They made offerings and human sacrifices throwing
into the incandescent crater children and maidens, sending them to “fetch water” during the drought seasons. Also, the aboriginal chiefs of the region, when solving important matters, asked for “secret advice” (Monexico in Nahualt language) to a sorceress who appeared inside the volcano. She was described as “an old woman with long and spiky hair, sharp fangs and breasts reaching her waist” 
It is thought that this sorceress of the volcano was Chalchiutlicue, thewater deity in Mexicanmythology whichwas inherited by the Nicaraos. This imagewas similar to that which the Spaniards had of the Devil which, added to the idea that all the aboriginal gods were product of the Devil and contributed to the belief that the volcano was the
mouth or gates of Hell. This led to Mercedarian Fray Francisco de Bobadilla climbing the volcano in 1529, where he erected a cross in order to exorcise what he called “The Mouth of Hell”.
The Dialogues of Saint Gregory (Book IV Chap.36) in which he states that volcanoes are the Mouths of Hell. This is evidence of the strong influence of the Classics and the Catholic Church over the thinking of this time.
The Carmelite Fray Antonio Vazquez, who visited Nicaragua at the beginning of the XVII century, speculates on the possible causes of the volcanic eruptions, thinking that they were the Earth’s vents from which the “fire of Hell” escaped. According to the theologians of the time, Hell was located at the centre of the Earth and according to the cosmographers it was exactly at 1030 and three quarters and a half leagues from where the humans lived!!! Furthermore, many of them pointed out that all known volcanoes, sometimes spat out fire smoke or ash and other times they didn’t. The big difference was that the Masaya volcano never ceased doing it and was in permanent activity. This led Friar Toribio Benavente (1541) to say “that the fire of the volcano of Nicaragua [Masaya] without fuel (…), must be the mouth of Hell and its fire must be supernatural and hellish, and the place from which the condemned are thrown by the demons” and further on, he makes a comparison with the Vulcano volcano (which in The Dialogues of Saint Gregory is named as the Mouth Of Hell into which King Theodoric was thrown) and adds “thus, if that one [Vulcano] is the Mouth of Hell, this one [Mayasa] not only seems to be the Mouth, but is Hell itself”. Lastly, in that time there were very popular versions told by sailors, who had visions of demons when they were near “those mountains that spit fire”. They also heard cries of the condemned or voices that mocked them and untied the ropes, lines and riggings if they didn’t make the sign of the Cross.
What I noticed from the name of this site was that its spelling sounds like messiah.