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EXHIBIT 5.1
CONSENT OF INDEPENDENT AUDITORS
The Sponsors and Trustee of Corporate Income Fund,
Monthly Payment Series--503, Defined Asset Funds:
We consent to the use in Amendment No. 1 to Registration Statement No. 333-95873
of our report dated November 17, 2000, relating to the statement of condition of
Corporate Income Fund, Monthly Payment Series--503, Defined Asset Funds and to
the reference to us under the heading "How The Fund Works--Auditors" in the
Prospectus which is a part of this Registration Statement.
DELOITTE & TOUCHE LLP
New York, NY
November 17, 2000
