How do you explain the case of Shanti Devi? Why did she have the memory of her past life? She didn't even know Jesus, so why did this happen? This has been affecting me a lot, and I even have no motivation to do anything in my life because of my weakened faith in the Lord.
Why would running into a point that you cannot currently answer weaken your faith in God? I don't know everything, so I expect to run into things that I cannot explain. But I can see if I can find answer without abandoning my faith.
We start with a simple fact: the Bible teaches that reincarnation does not happen. See: Reincarnation. If we accept that fact, then we should open our eyes to the possibility that there is another explanation of what happened that does not involve reincarnation. We might not be able to prove that this actually did happen, but if there are other possibilities, then it no longer is a proof of reincarnation.
The Case of Shanti Devi
Shanti Devi was born in 1926 in Delhi, India. In the 1930's she began claiming that her real home was in the town of Mathura, where her husband lived. She also stated in school that she was married and died ten days after giving birth to a child. When interviewed she used a few words from the Mathura dialect and said the name of her husband was Kedar Nath.
Investigations later showed that Kedarnath Chaubey frequently traveled to Deli to purchase cloth and while there would purchase sweets near Shanti Devi's home. First notice that early on she got the name slightly wrong for her husband. She also made some mistakes concerning her husband's shop location and the color of his house.
A cousin of Kedarnath visits the girl at Shanti Devi's uncle's invitation. She claims to recognize the cousin, but she doesn't know his name. When asked why she doesn't know his name she said, "I recognized your features!" The cousin found out that she knew Kedarnath Chaubey's name and that he had an older brother and a living father. Remember that her uncle wrote to the man. She knew that Kedarnath's house was on Chaubey Street, but when asked about where on the street the house was located, she said that there was a grocery shop in front of the house, which was incorrect. She was asked if she had ever lent money. She said she did not know, but the wife had lent money. She mentioned that she had hid money in the grounds of the house, but it later is found out that Kedarnath had already dug it up. It is a Hindu tradition to bury money, by the way. When asked when and how she died, she said she did not know.
When Kedarnath is brought to her, she recognizes him and correctly identifies his older brother who came with him. Later she correctly identifies an old man in front of Kedarnath's house as her father, but when she was brought to the house of her parents, she confused her aunt for her mother.
What it appears is that this little girl overheard Kedarnath talking about his life with someone by the candy shop and started imagining that she was his reincarnated wife. As people came to verify the story she managed to make some good guesses based on facial features, but those interviewing her were also accidentally feeding her the correct responses. As news began to be spread about her, more details are given to her and her story becomes more refined. Yet, to be unable to identify her own supposed mother tells us that while she was good at guessing based on facial features, there were limitations. Kedarnath's family looked similar and you could refine it by ages, but she had nothing to use as a base for Kedarnath's dead wife's family.
The conclusion is that there is no evidence of reincarnation here. Yes, a number of Hindu people really want to believe it is true, but that is not evidence of itself.