EXHIBIT NO. 5.1












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LOCKE PURNELL RAIN HARRELL
2200 Ross Avenue, Suite 2200
Dallas Texas 75201
(214) 740-8000
FAX: (214) 740-8800

                                January 31, 1997

Comstock Resources, Inc.
5005 LBJ Freeway, Suite 1000
Dallas, Texas  75244

        Re: Registration of 120,000 shares of Common Stock pursuant to a
            Registration Statement on Form S-8

Ladies and Gentlemen:

     We have acted as counsel for Comstock Resources, Inc., a Nevada corporation
(the "Company"), in connection with the registration under the Securities Act of
1933, as amended (the "Securities Act"), pursuant to a Registration Statement on
Form S-8 (the "Registration Statement"), of 120,000 shares of Common Stock, $.50
par value, of the Company (the "Common  Stock"),  of which 100,000 shares are to
be  issued in  connection  with the  Company's  Non-employee  Director  Retainer
Election  Plan (the "Plan"),  and 20,000  shares are to be issued  pursuant to a
Nonstatutory  Stock Option  Agreement dated May 15, 1996 between the Company and
Herbert C. Pell,  III (the  "Option  Agreement")  as  further  described  in the
Registration Statement.

     We  have  made  such  inquiries  and  examined  such  documents  as we have
considered  necessary  or  appropriate  for the  purpose of giving  the  opinion
hereinafter set forth.  We have assumed the genuineness and  authenticity of all
signatures  on  all  original  documents,  the  authenticity  of  all  documents
submitted to us as  originals,  the  conformity  to  originals of all  documents
submitted  to us as copies and the due  authorization,  execution,  delivery  or
recordation of all documents where due  authorization,  execution or recordation
are prerequisites to the effectiveness thereof.

     Based upon the foregoing, having regard for such legal considerations as we
deem relevant,  and assuming,  with respect to the shares of Common Stock issued
under the Plan and pursuant to the Option  Agreement (i) the  availability  of a
sufficient number of shares of Common Stock authorized by the Company's Articles
of Incorporation  then in effect, and (ii) no change occurs in applicable law or
the  pertinent  facts,  we are of the opinion that the 120,000  shares of Common
Stock  that may be issued  and sold by the  Company  from time to time under the
Plan or  pursuant  to the Option  Agreement,  as  described  in the Plan or such
Option Agreement,  will upon issuance and delivery against payment therefor,  be
duly authorized and legally issued, fully paid and nonassessable.

     We hereby  consent to the filing of this  opinion with the  Securities  and
Exchange  Commission  as  an  exhibit  to  the  Registration  Statement.  By  so
consenting,  we do not  thereby  admit that our firm's  consent is  required  by
Section 7 of the Securities Act.

                             Very truly yours,

                             LOCKE PURNELL RAIN HARRELL
                             (A Professional Corporation)


                             By:   /s/ JACK E. JACOBSEN
                                   Jack E. Jacobsen


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