Short answer. No, not automatically. Under Article 938, a legacy or devise left to a creditor is not applied to the debt owed unless the will expressly says so. You can generally keep the legacy and still collect the debt separately, unless the will clearly states the legacy is meant to settle it.
What the law says
A legacy or devise made to a creditor shall not be applied to his credit, unless the testator so expressly declares.
Civil Code, Article 938 — A Legacy to a Creditor. Read the full provision →
What the law says
the creditor shall have the right to collect the excess, if any, of the credit or of the legacy or devise
Civil Code, Article 938 — A Legacy to a Creditor. Read the full provision →
The legacy and the debt are presumed separate
Article 938 starts from a presumption in the creditor's favor: a legacy or devise made to a creditor shall not be applied to his credit, unless the testator so expressly declares. So if your father simply named you in his will and left you money or property, without saying that gift was meant to settle what he owed you, the two are treated as independent. You take the legacy as a gift, and you can still pursue payment of the debt on its own terms, because the law does not assume a testator meant to use a bequest as a quiet way of paying an obligation.
When the will does say the legacy pays the debt
The result changes only if the will contains an express statement to that effect. Even then, the creditor is not shortchanged: the creditor shall have the right to collect the excess, if any, of the credit or of the legacy or devise. If the debt is larger than the legacy, you can still collect the difference as an ordinary creditor of the estate. If the legacy turns out to be worth more than the debt, you keep the extra value as a bequest. Either way, you are never limited to whichever figure is smaller.
Why the law will not assume an offset
This rule protects two different relationships that happen to involve the same two people. A debt is an obligation the testator was already legally bound to pay; a legacy is a fresh act of liberality the testator chose to make. Collapsing them by default would let a testator quietly discharge a real debt by dressing it up as a gift, leaving the creditor worse off than expected without ever saying so plainly. Requiring an express declaration forces that intention into the open, where the creditor-heir can see it, rather than leaving it to be inferred from silence.
What to check in the will
Because everything turns on the will's actual wording, the practical question is whether the document names the debt and says the legacy is given in payment or satisfaction of it. General or vague language pointing toward you as a beneficiary is not enough to trigger the exception. If the will is silent on the connection between the two, Article 938 treats them as unrelated, and you are entitled to both the legacy and full payment of what your father owed you.