delivered the opinion of the Court.

Appellant Ángel L. Arroyo brought a summary proceeding in the Superior Court, Mayagüez Part, to foreclose a mortgage constituted by deed No. 87 of July 9, 1957 before Notary Eudaldo Báez García by the spouses Antero Díaz Se-garra and Rosa María Rios in favor of the holder of a note to bearer for the principal sum of $3,000, interest thereon at the rate of nine per cent annually, and an additional credit of $300 for costs, expenses, and attorney’s fees in the event of judicial sale, on four rural properties owned by the latter situated in the ward of Ovejas of the Municipality of Añasco, having an area of 24, 14, 8, and 5 cuerdas. Process having been served pursuant to law without the debtors having deposited the sums due which on the filing date of the proceeding amounted to $3,772.50, appellant sought and obtained an order to sell at public auction on the basis of the assessment stated for each property in the mortgage deed “which will serve as basis for the first auction sale.”

The only bidder who appeared at the first and only auction sale was the foreclosing creditor himself, who offered for the properties the same amounts in which they were appraised by the contracting parties, to wit : $1,075 (24 cuer-das), $875 (14 cuerdas), $675 (8 cuerdas), and $675 (5 cuerdas). No better offer having been made, the bid was awarded to him and the corresponding deed of judicial sale executed by the marshal in favor of appellant.

The deed having been presented in the Registry of *346Property of Mayagüez, record was denied on the ground that the court had ordered the sale at public auction of the mortgaged properties on the basis of the assessment set forth in the mortgage deed, the amounts of which were less than the preferred credits which encumbered each property1 and which were awarded at the first auction sale for the assessed values,2 “thereby voiding the summary proceeding pursuant to arts. 128 of the Mortgage Law and 172 of the Regulations of the Mortgage Law, and the holding in the cases of Cintrón et al. v. Banco Territorial y Agrícola, 15 P.R.R. 495, and Hernandez v. Registrar, 66 P.R.R. 814.” The present administrative appeal was timely taken from such denial.

1. When the Mortgage Law for Overseas Provinces which took effect in Puerto Rico on October 5, 1893 was enacted, one of the most important reforms incorporated in the former law in force since May 1, 1880 consisted in the adoption of the summary proceeding to collect the mortgage *347credits,3 one of the basis of which was the prior assessment of the mortgaged property. Until then, according to art. 141 of the Act of 1880, “upon expiration of the period for payment of the debt, the creditor may request an order to foreclose all the mortgaged properties... ,” in which case there shall be followed the distraint proceeding provided in the Law of Civil Procedure, § 1483 et seq. of which required the appraisal of the properties. Section 1516 of the Law of Civil Procedure provided that “if the execution should have been issued at the instance of a second or third mortgage creditor, the amount of the 'preferred mortgage credits for which the estate sold is liable shall be deposited in the establishment provided therefor, and the balance shall be delivered without delay to the execution creditor, if the same *348should not exceed or be less than the amount of his credit.” 4

The Act of 1893 incorporated in art. 127 the prerequisite of appraisal, providing that in the mortgage shall appear the value of the estate as appraised by the contracting-parties, which shall serve as a basis for the “only judicial sale” in case of foreclosure. For a more complete historical exposition, see Land Authority of P.R. v. Registrar, 82 P.R.R. 327, 329-32 (1961). In the following art. 128 it was provided that “if there is no bidder, the claimant may demand that the property be awarded to him, being responsible for all prior 5 liens, if there be any,” and that “when an estate is sold at public auction at the instance of a second or subsequent mortgagee or common creditors, the sale shall be declared null and void if a sufficient sum is not offered to cover all previously recorded debts, including the interest which it appears is stipulated according to the Registry.” And in the third paragraph of art. 172 of the Regulations it was provided that “when the estimate of the property agreed to in *349the instrument constituting the loan, by virtue of which the proceedings are held, exceeds the amount of the preferred obligations secured by the property, said estates shall be inserted in the notices as the amount acceptable at the public sale,” but “when the preferred obligations exceed it, their total amount shall be the minimum acceptable at the public sale.”

The Act Relating to Judgments and the Manner of Satisfying Them (Sess. Laws, p. 115; 32 L.P.R.A. §§ 1140-47) was enacted on March 9, 1905 and had the effect of repealing art. 127 supra, and it was therefore unnecessary to appraise the mortgage property for the purposes of the auction sale, which was carried out without a minimum basis. In fact, the summary foreclosure proceeding was effective only as of the filing of the initial writing until payment was tendered. Carrión v. Registrar, 43 P.R.R. 104 (1932); Iglesias v. Registrar, 43 P.R.R. 18 (1932); Porto Rican Leaf Tobacco Co. v. Registrar, 23 P.R.R. 470, 471 (1916); Cintrón et al. v. Banco Territorial y Agrícola, 15 P.R.R. 495, 510 (1909); Bolívar et al. v. The Registrar of Property, 13 P.R.R. 362 (1907); Banco Territorial y Agrícola v. Erwin, District Judge, 10 P.R.R. 388 (1906); Giménez et al. v. Brenes, 10 P.R.R. 124 (1906). In the procedure followed — without being subject to appraisal for the auction sale — and out of deference to the principle that the vested rights acquired by preferred creditors could not be affected — any award made was subject to the prior credits.

Owing to the many abuses committed as a result of the lack of appraisal, with the consequent adjudication or award for derisive amounts, the Legislative Assembly by Act No: 69 of May 2, 1931 (Sess. Laws, p. 432) amended art. 127 as follows:6

*350“The mortgage deed shall state the value at which the contracting parties appraise the estate, in order that it may sene as a basis for the first public sale which may be made, in the event that, the term of the loan having expired, the registry of the property does not show the payment of said loan.”

In § 2 of that Act it was stated that the provisions of the Act of March 9,1905, in so far as they conflict with the provisions of art. 127, were repealed.

It may be noted that the latter wording of art. 127 eliminates the reference to the only sale which appeared in the Act of 1893 and substitutes the same by first public sale, and further, by the addition of the second and third paragraphs, it expressly provides the minimum amount which shall prevail if a second sale or subsequent sales may be held. In connection with these subsequent sales, these two paragraphs are intertwined with paragraphs 6 to 9 of art. 172 of the Regulations7 which, we repeat, are not in force.

*351So far the historical review of the legislation on the appraisal of the mortgaged property.

2. The problem of reconciling the provisions of arts. 127 and 128 of the Mortgage Law with art. 172 of the Regulations is most difficult.8 This is due to their connection with other provisions of the Spanish Law of Civil Procedure which, we know, does not govern in Puerto Rico, save for a few exceptions. On the other hand, it is not clear whether the lawmaker attempted to adopt a system of subsistence, of the encumbrances or liens when the property is awarded to the second or subsequent mortgagees, or if the system of purging the preferred credits consecrated in the foreclosure proceeding provided in the Law of Civil Procedure shall prevail — § 1516 supra. We deem it advisable to make brief reference to both systems.

In the system of subsistence or maintenance of the preferred mortgages the foreclosure does not produce their extinguishment, but they are kept alive; in the purging system the preferred credits are extinguished by the foreclosure, and they are paid off with the price of the auction sale. Hence, the necessity that the minimum price cover, at least, the amount of these preferred obligations. As Roca Sastre in*352dicates (IV Derecho Hipotecario 870, 1954 ed.), “the property .passes clear and free from mortgages, that is, cleansed from mortgages, to the purchaser or acquirer.” In advocating the system of subsistence, Jaime Guasp, Professor of Procedural Law of the University of Madrid, states as follows:9

“It is not difficult to understand the inconveniences which such a system [purgation] entails, particularly for an efficient development of the territorial credit. In the first place, the owner of a second or subsequent mortgage ran the risk, at the time of foreclosure, that his guaranty be eliminated by a possible unfavorable result of the auction sale; in the second place, the preferred creditor saw his capital investment disappear by a liquidating operation which even change the nature of the right of which he is owner. That explains why not only in Spain but also in other countries the principle of the liquidation or extinguishment of the encumbrances has given way to the opposite principle: the principle of subrogation whereby such preferred encumbrances are transferred to the new acquirer of the property.”

Registrar Eduardo Martínez Mora sums up .the principal arguments in favor of the reform of 1909 as follows:10

(1) the knowledge of the prior mortgage which the foreclosing creditor already has; (2) the second mortgage is not.covered by the property, but by the balance of the value of the first mortgage; (3) the preferred creditors are not a party to the proceedings;11 (4) the indifferentiation which ought to exist between the judicial and the extrajudicial alienation (he *353refers to that provided in art. 129 of the Spanish law). On this same subject, see 18 Revista Crítica de Derecho Inmobiliario 822 (1945); 17 id. 450 (1944); 15 id. 455 (1942); and 5 id. 117 (1929); V Revista de Derecho Privado 190 (1918).

In Spain the mortgage reform of 1909 abandoned the purge system of the Law of Civil Procedure and adopted that of subsistence of preferred liens and imposed the subrogation of the person of the purchaser in the payment of the personal credit secured by the mortgage.12 To that effect art. 131 provides as follows:

“Eighth. The notices shall state: that the record and the certificate of the Registry referred to in rule 4 shall be available in the office of the notary public; that it shall be deemed that every bidder accepts the title as good, and that the 'prior charges, and liens and those having preference — if any — over the credit of the claimant shall subsist, it being understood that the highest bidder accepts them and subrogates himself in their responsibility, and that the price of the sale shall not be applied to their extinguishment.

“Ninth. The basis agreed upon in the mortgaged deed shall serve as basis for the auction sale and no bid shall be admitted which is less,than such basis.

“Tenth. If there be no admissible bid at the first sale, the creditor may request that the property or properties be awarded to him in payment of his credit for the sum of the former, accepting the subsistence of the prior and the preferred charges, if any, and subrogating himself in the obligation to satisfy them.

“Eleventh. If the creditor does not accept the award, he may request that a second sale be held, the basis of which shall be 75 per cent of the former, and no bid lower than such basis shall be admitted; and if at such sale there be no admissible bid either, he may request that it be awarded to him for *354the basis of the second sale and with the same condition contained in the preceding rule.

“Thirteenth. It shall be stated in the act of the sale that the highest bidder accepts the obligations set forth in rule 8, otherwise the bid shall not be awarded to him.” [Italics ours.]

Guided by the cardinal principle that the foreclosure of a credit of a lower rank should not prejudice a preferred credit, with a flexible criterion of interpretation of mortgage legislation which may respond to the development of our dynamic economy, promote contracting and impress the territorial credit with stability, and in consonance with the respect due the covenant between the debtor and the creditors; considering, further, that § 1516 of the Spanish Law of Civil Procedure 13 is not in force in Puerto Rico, we are i bound to hold that when the foreclosing creditor adjudicates to property to himself at the first auction sale for the appraised value, it is not necessary to fix as minimum basis the amount of the preferred obligations, even though the latter exceed the contractual appraisal if the foreclosing creditor, even if he is a second creditor, assumes and answers for the preferred liens and charges — first paragraph of art. 127 and third paragraph of art. 128. And in this assumption neither the fourth paragraph of art. 128 nor the third paragraph of art. 172 of the Regulations comes into play.

The judicial surgery which by way of interpretation we have been compelled to perform in order to give meaning to the legal provisions involved and give stability to the prevailing practice in the summary foreclosure proceeding, emphasizes once again the undeferable and urgent need to review without delay the existing mortgage legislation. On *355three different occasions in the short lapse of two years this Court has referred to the incompatibility of precepts which still appear in the Mortgage Law and which do not conform to a scientific and duly synchronized plan — Land Authority v. Registrar, supra; Vechini v. Registrar, supra; and the present administrative appeal. The task is not too difficult if we profit, for what it is worth, from the experience of Spain with its reforms of 1909 and 1946 and the new Regulations of 1959. It is fitting to point out that this reform should be aimed at resolving numerous problems pertaining to the registry confronting our increasing industrial economy and the recent urban expansion with their varied credit and finance problems. Lastly, and no less important, it is incumbent on those first called upon to interpret this law to do it in such a way as to facilitate rather than to obstruct the transactions, giving more attention to substance than to theoretical details and having in mind the principle that resort is had to the registry for protection and not for prejudice.14

The decision appealed from will be reversed and the registration sought is ordered.