Gnomesword is a bible study tool for Linux. Latest version known as Xiphos will available now, But I have tested gnomesword and found it is good and stable. By default it is in arabic bible with english commentary. It is open-source software, and available free-of-charge to all.
To install in ubuntu
System->Administration->Synaptic package manager and search for gnomesword
also add sword-language-pack-en for English bible , lot of athor language support also available
open a terminal and type
$ sudo apt-get install gnomesword sword-language-pack-en