How does belief in souls or the afterlife influence emotions related to the death of others? Background: Once when I heard of a death in my locality, I was happy rather than feeling grief because I was thinking that the soul of that dead person has achieved the truth.  

How does belief in souls or the afterlife influence emotions related to the death of others?
Religion and spirituality provide coping strategies and relief for those who experience bereavement to help negate or provide incentive for surviving the trauma. Soul based beliefs tend to encourage the idea of an eventual reunification with the loved one. 

Since this person was not a dear loved one your purely religious coping strategy is fine and perfectly normal. However I would be concerned and advise you to seek a doctor's help if you had the same absence of grief during the bereavement of a loved one.  

The role of religion in dealing with bereavement is not well researched because its difficult to draw empirical data from unempirical relief. Especially with it being such a universally private and very tender time in a persons life. I did find one chapter from a book which provided a solid set of guidelines and so cite bellow. 


  People often report that their religion or spirituality was helpful or even essential
  for getting through and recovering from their grief (see Wortmann &amp; Park, 2008,
  for a review) in spite of the lack of solid empirical evidence that this is so. indeed, there are strong theoretical rationales for positing that religion and spirituality can strongly impact the process of grieving.for many individuals, religion or spirituality underlies their general approach to life and forms the system of meaning through which they experience and understand the world and operate on a daily basis, making the universe seem benign, safe, just, coherent, and, ultimately, controllable (Park et al., in press). Clearly, when facing highly stressful experiences such as the death of a loved one, this meaning system will influence their responses to it.
  
  Religious and spiritual perspectives provide many resources for understanding and coping with loss. Many traditions provide perspectives on death, such as viewing loss as illusory rather than real or as a necessary step toward a more glorious future. Several predominant religious belief systems hold out possibilities for everlasting life and for reunification with the lost loved one after one’s own death (Greeley &amp; hout, 1999). Beliefs in a soul that is separate from and persists after the death of the physical body also allows for the possibility of remaining in contact with the deceased (Benore &amp; Park, 2004), a commonly reported experience in the United States (klugman, 2006). in addition, religious and spiritual traditions offer a panoply of coping resources for dealing with death.
  
  these resources include social support from pastors and fellow congregants, and many rites and rituals to assist mourners through the process of grieving. for example, all religious traditions prescribe specific prayers, behaviors, and funeral ceremonies to deal with death, which comfort mourners and give them a sense of structure and a sense of belonging to a broader community (Wuthnow et al.,1980).
  
  through these resources, individuals may find solace and comfort and, over
  time, work through their grief in ways that allow them to find peace and acceptance
  and to return to their normal daily lives (halifax, 2008). of course, normal life is forever changed with the loss of a loved one, and people often carry a lingering sense of sadness and longing for the lost person (Stroebe, Abakoumkin, &amp; Stroebe, 2010).
  
  importantly, mitigating negative outcomes is not the only possibility represented
  by religious and spiritual approaches to bereavement. in fact, many religious and spiritual traditions hold that the suffering experienced through bereavement can be an impetus for transformative spiritual experience. Such a perspective holds that to deny grief is to rob one of the heavy stones that will eventually be the ballast for the two great accumulations of wisdom and compassion. indeed, grief is a vital part of our very human life, an experience that can open compassion, and an important phase of maturation giving depth and humility to life; it can be regarded as a gift. Grief can ruin or mature us.
  
  like the mother who bathed her dead baby in her breast milk, grief can remind us not to hold on too tightly as it teaches us tenderness and patience with our own suffering. Many bereaved individuals report extensive personal growth following bereavement, including increased appreciation for life, enhanced spirituality, and closer interpersonal relationships, and religious and spiritual pathways are a common pathway to this transformative growth (Park, 2005).


-Religion and Spirituality in Adjusting to Bereavement