Formalities, presumption in remission of obligation

Article 1270 of the Civil Code states that express remission is subject to the formalities as donations, to wit:
ART. 1270. Condonation or remission is essentially gratuitous, and requires the acceptance by the obligor. It may be made expressly or impliedly.

One and the other kind shall be subject to the rules which govern inofficious donations. Express condonation shall, furthermore, comply with the forms of donation. (1187)
The express condonation of a movable or personal property may be made either orally or in writing. Under Article 748 of the Civil Code, if the value of of the personal property donated exceeds five thousand pesos, the donation and the acceptance shall be made in writing. Otherwise, the donation shall be void.

Moreover, in the express condonation of an immovable property, in order for the donation to be valid, it must be made in a public document, specifying therein the property donated and the value of the charges which the donee must satisfy. The acceptance may be made in the same deed of donation or in a separate public document, but it shall not take effect unless it is done during the lifetime of the donor. Article 749 provides that if the acceptance is made in a separate document, the donor shall be notified thereof in an authentic form, and this step shall be noted in both instruments. 

Moving on, Articles 1271 and 1272 provide for the presumption of condonation or remission, thus:

ART. 1271. The delivery of a private document evidencing a credit, made voluntarily by the creditor to the debtor, implies the renunciation of the action which the former had against the latter.

If in order to nullify this waiver it should be claimed to be inofficious, the debtor and his heirs may uphold it by proving that the delivery of the document was made in virtue of payment of the debt. (1188) 

ART. 1272. Whenever the private document in which the debt appears is found in the possession of the debtor, it shall be presumed that the creditor delivered it voluntarily, unless the contrary is proved. (1189)

If there is a delivery of a private document evidencing a credit and the delivery was voluntarily made by the creditor to the debtor, there will be an implied renunciation except when the contrary is proved. However, it must be noted that the presumption of remission is prima facie and it can be disproved by showing the absence of voluntary delivery of the document to the debtor. Remission can be nullified on the ground that it was inofficious. 

In Article 1272, if the private document in which the debt appears is found in the possession of the debtor, there is a presumption that it has been voluntarily delivered by the creditor unless the contrary is proved. In Article 1273, if the remission was only to the extent of the accessory obligation, the principal obligation is not extinguished. This is because the principal obligation may exist without the existence of any accessory obligation; but the latter cannot.

Furthermore, when a thing is pledged and there has been a delivery of such thing or the thing pledged is found in the possession of the debtor, or of a third person who owns the thing, there is a presumption of renunciation of accessory obligation. This is discussed in Article 1274 of the Civil Code.