When Beryl Thompson studies the Bible, she does not pick up a well-worn leather book. Instead, she switches on an Apple computer.
The 70-year-old Bible teacher is one of several hundred people now studying the Scriptures using a computer program developed by Bible Research Systems, a small Austin, Texas, firm. The company's program, dubbed ''The Word Processor,'' is the first to provide the entire Bible in a form that can be used on a home computer.
''I am finding it very useful,'' teacher Thompson says. ''It is much simpler to use'' than traditional Bible study methods.
The new scriptural software in effect turns her computer into an electronic concordance. She can ask the machine, for example, to make a list of every place where a word or phrase appears in the Bible. When the index appears on the computer's video screen, she can ask the machine to display the entire verse in which the words appear. The verses above and below the citation can also be read.
And the system's custom-made indexes can be stored, so earlier research on a given topic can be retrieved. ''Otherwise you would have to go back to a concordance'' and redo the research, the Modesto, Calif., resident notes. In addition, the program will compare entries in two indexes to identify passages that appear in both, highlighting relationships between subjects.
Until now, computerized Bible research has been ''tied to academic institutions,'' says Harold Scanlin, special secretary in the American Bible Society's translations department. Bible scholars can make special arrangements with universities to use computer files containing not only English translations but also original texts in Hebrew and Greek.
Development of computerized home Bible study aids was limited by ''the enormous amount of information that needs to be put (into a program) compared to the size of the potential market. It is not profitable'' in the way other programs of similar complexity would be, Mr. Scanlin notes.
In early 1981, former Intel Corporation executives Bert Brown and Kent Ochel took up the challenge of compressing the Bible's 4.5 million characters to fit on a handful of computer storage disks.
''Our personal motivation is wanting to help people read The Word more,'' says Brown, cofounder of Bible Research Systems. While the software is considered reasonably priced at $159.95, the venture is intended to make a profit.
One of the programmers' toughest challenges was finding a way to enter the Bible into a computer database. Brown and Ochel finally convinced a Bible publisher to lend them computer tape used to typeset the King James version for a conventional book.
But getting the text into computer storage was not the last hurdle. If the 14 ,000 words in the Scriptures were simply copied onto computer storage disks (which resemble 45 r.p.m. records), they would fill 42 disks. So the two men developed a computer shorthand for storing the most frequently used words (To the user, however, the text appears on the screen unabbreviated). As a result, the entire Bible can be stored on both sides of 8 disks.
To search the entire Bible for a word or phrase, a user must change storage disks. The amount of shifting between disks required depends on the kind of computer storage equipment the user owns. But a low-cost 51/4-inch floppy disk holds a lot of information. For example, the book of Psalms takes one side of a disk and the Gospels take a little more than one side.
''Searching a whole disk takes about three minutes,'' says John Holmes, owner of Apple Soft Business Ware, a Charlotte, N.C., firm specializing in computer databases and their applications.
Religious computer owners are not the only ones who want a computer's help in studying the Bible. A significant number of buyers have '' an academic interest'' in the Bible as a work of history or literature, according to Brown. The program also is being purchased by schools and public libraries.
Roughly one million people have personal computers which can use The Word Processor, although the number of potential customers is far smaller. The program now runs on Apple and Radio Shack personal computers and will soon be available for IBM machines.
Still, local computer stores are wary about stocking religious items. ''I offered to give it to (several stores) on consignment and some wouldn't even put it on their counter,'' Holmes notes.
Some computer stores do carry the program, but most sales have been by mail order from Bible Research (8804 Wildridge Drive, Austin, Texas 78759). The program has been on the market since February.
To date, Bible Research has the computerized Bible market to itself. But at least one other company is ''in the process of developing '' a similar program offering another version of the Bible, Scanlin says. Brown says a more modern version was his first choice, but the King James version is the only one which did not present copyright hurdles.
Bible Research Systems plans to offer additional computerized Bible study aids, such as a version of Nave's Topical Index due out in September.