Guru sahib was only participating in the havan practice because the Hindu pandidts came up to guru with a scheme. But guru ji was Jaani Jana they knew everything. When the news got around that guru gobind singh ji was going to start this new initiation (Amrit) the pandit came up with a plan to try and kill baba ajit Singh ji as they thought baba ji would be the next guru. They came up to guru ji and insisted that he would do havan to Candi goddess as in Hindu ithihas whenever something very big was about to happen they would preform havan just like we do ardas. Raam preformed havan before going to yudh with raavan. Guru ji then (knowing everything) agreed and they climbed up naina Devi Pahaar. When the pandit was doing havan nothing happened. Chandi was never summoned and nothing amazing happened. After the pakhand had gone on for about half an hour the pandit then devised his plan. He said guru ji needed to sacrifice something dear to him to please the goddess. His eye rested upon baba ajit Singh ji, guru ji then with a smile said "who could be more dear to me than you, who is going through all this trouble to summon chandi for me" the pandit then realising guru ji was very intelligent ran off. Guru ji then threw all the little tuff and small artefacts that made a huge fire. The pandit would fool people by getting them to pay money and throwing everything into the fire to create a large flame and then say "chandi is here" the true practice to praise the goddess had turned into a business. Guru ji then spent many months up naina Devi preforming tapasiya and havana. from miles away you could see loads of thunder storms and lightning etc. Then when guru ji came back down they asked him if he had summoned chandi. Guru ji took out his Sirohi kirpan and said this is chandi. That's where the name for chandi comes from for the kirpan
pull chuk maaf, if someone very much more knowledgeable than me knows the name of the pandit please enlighten the sangat on this forum, including me!