Committing suicide is a grave sin which is forbidden by Islam. A Muslim’s killing himself/herself is a bigger murder and sin than killing another person. Thus, Islamic scholars have disputed whether the funeral prayer of a person who has committed suicide is performed or not. This discussion is not made for a murderer who killed someone. A murderer’s funeral prayer is performed.
This took me by surprise. Hence my question:
Question: Is suicide a worse sin than murder?
Essentially I'm asking for this claim to be confirmed (or refuted), and either way, identify who is making this claim. It is possible that the answer to this question varies from sect to sect (so please acknowledge it if your answer is limited to some school of thought). It's also possible this claim is limited to a small number of scholars.
Google yielded this:
For Islam, suicide is always forbidden; some regard it as worse than murder. -- Abdal-Hakim Murad, Bombing Without Moonlight, 2004
This webpage references: 'Abdallah ibn Qutayba, 'Uyun al-akhbar (Cairo, 1348/1930), iii, 217. I don't believe I have access to this book, but it would be a good place to start.
Just to indicate this is not a "once off" claim; similar claims are made in e.g.: (a) Benedict Auer, Jessy A. Ang, Torment of the Soul: Suicidal Depression and Spirituality, 2007, p. 38, (b) John L. Esposito, The Future of Islam, 2010, p. 99, and (c) Nils Retterstøl, Suicide: A European Perspective, 1993, p. 13.