The name of the lord in Sikhism is Waheguru maeaning the wondorous Lord who dispells darkness. When Guruu Nanak was bathing in the river Vayee and disappeared After three days Guru Nanak appeared at the same spot from where he had disappeared. He was no longer the same person he had been and there was a divine light in his eyes and his face was resplendent. Guru Nanak was in the Holy Communion with God. The Lord God revealed Himself to Guru Nanak and enlightened him. Then onwards, Guru Nanak began extensive travel to spread the message of God in the form of musical hymns. Guru Nanak gave us naam and with it saved us from the noose of death.
Sin is ever increasing throughout the World it is the Kali Yuga (Dark Age). The Guru will come and give us Satya Yug (Golden Age) but at the end of ever Kali Yuga there is a great amount of destruction and"cleansing". When the Guru will come it is his own will. Although the time is soon.
People suffer and experience sadness according to your own karma in this life and the previous ones. Unfortunately Guru ji did not give us the knowledge of our previous lives through all the various species weve been born through and as humans, im sure if we knew we would all strive to meditate on Naam and love it

and escape the transmigration of the Soul.