Similarly, the path of the offer of life resembles that of heroic virtues because there is a heroic act of charity (the gift of self) inspired by Christ’s example, but it is distinguishable because it is not the expression of a prolonged exercise of virtues and, in particular, of heroic charity. However, it requires an ordinary exercise of Christian life, which makes possible and comprehensible the free and voluntary decision to give one’s own life in a supreme act of Christian love, which surpasses the natural instinct of self-preservation, by imitating Christ, who offered himself to the Father for the world, on the Cross.

https://www.catholicculture.org/news/headlines/index.cfm?storyid=32132

But he was NOT a martyr.  JP2 invented "martyr of charity", no such designation had EVER existed in the church prior to JP2.  He just dreamed that one up for his own mysterious reasons.  True Roman Catholics do not fabricate excuses for anything, much less a "Pope" daring such a thing.

Art. 2

The offer of life, in order that it be valid and effective for the beatification of a Servant of God, must respond to the following criteria:
a) a free and voluntary offer of life and heroic acceptance propter caritatem of a certain and untimely death;
b) a nexus between the offer of life and premature death;
c) the exercise, at least as ordinarily possible, of Christian virtues before the offer of life and, then, unto death;
d) the existence of a reputation of holiness and of signs, at least after death;
e) the necessity of a miracle for beatification, occurring after the death of the Servant of God and through his or her intercession.

http://w2.vatican.va/content/francesco/en/apost_letters/docuмents/papa-francesco-lettera-ap_20170711_maiorem-hac-dilectionem.html

The sacrosanct Roman Church, founded by the voice of our Lord and Savior, firmly believes, professes, and preaches one true God omnipotent, unchangeable, and eternal, Father, Son, and Holy Ghost; one in essence, three in persons; Father unborn, Son born of the Father, Holy Spirit proceeding from Father and Son; that the Father is not Son or Holy Spirit, that Son is not Father or Holy Spirit; that Holy Spirit is not Father or Son; but Father alone is Father, Son alone is Son, Holy Spirit alone is Holy Spirit. The Father alone begot the Son of His own substance; the Son alone was begotten of the Father alone; the Holy Spirit alone proceeds at the same time from the Father and Son. These three persons are one God, and not three gods, because the three have one substance, one essence, one nature, one divinity, one immensity, one eternity, where no opposition of relationship interferes.

“Because of this unity the Father is entire in the Son, entire in the Holy Spirit; the Son is entire in the Father, entire in the Holy Spirit, the Holy Spirit is entire in the Father, entire in the Son. No one either excels another in eternity, or exceeds in magnitude, or is superior in power. For the fact that the Son is of the Father is eternal and without beginning; and that the Holy Spirit proceeds from the Father and the Son is eternal and without beginning.” Whatever the Father is or has, He does not have from another, but from Himself; and He is the principle without principle. Whatever the Son is or has, He has from the Father, and is the principle from a principle. Whatever the Holy Spirit is or has, He has simultaneously from the Father and the Son. But the Father and the Son are not two principles of the Holy Spirit, but one principle, just as the Father and the Son and the Holy Spirit are not three principles of the creature, but one principle.

Whoever, therefore, have adverse and contrary opinions the Church disapproves and anathematizes and declares to be foreign to the Christian body which is the Church. Hence it condemns Sabellius who confuses the persons and completely takes away their real distinction. It condemns the Arians, the Eunomians; the Macedonians who say that only the Father is the true God, but put the Son and the Holy Spirit in the order of creatures. It condemns also any others whatsoever who place grades or inequality in the Trinity.

Most strongly it believes, professes, and declares that the one true God, Father and Son and Holy Spirit, is the creator of all things visible and invisible, who, when He wished, out of His goodness created all creatures, spiritual as well as corporal; good indeed, since they were made by the highest good, but changeable, since they were made from nothing, and it asserts that nature is not evil, since all nature, in so far as it is nature, is good. It professes one and the same God as the author of the Old and New Testament, that is, of the Law and the Prophets and the Gospel, since the saints of both Testaments have spoken with the inspiration in the same Holy Spirit, whose books, which are contained under the following titles it accepts and venerates.

Besides it anathematizes the madness of the Manichaeans, who have established two first principles, one of the visible, and another of the invisible; and they have said that there is one God of the New Testament, another God of the Old Testament.

It believes, professes, and proclaims that one person of the Trinity. true God, Son of God born from the Father, consubstantial and coeternal with the Father, in the plenitude of time which the inscrutable depth of divine counsel has disposed for the salvation of the human race, assumed true and complete human nature from the immaculate womb of the Virgin Mary, and joined with itself in the unity of person, with such unity that whatever is of God there, is not separated from man, and whatever is of man, is not divided from the Godhead; He is one and the same undivided both natures, God and man, remaining in their own peculiar properties, God and man, Son of God and Son of man, equal to the Father according to divinity, less than the Father according to humanity, immortal and eternal from the nature of divinity, passible and temporal from the condition of assumed humanity.

It firmly believes, professes, and proclaims that the Son of God in the assumed humanity was truly born of the Virgin, truly suffered, truly died and was buried, truly rose again from the dead, ascended into heaven, and sits at the right hand of the Father, and will come at the end of time to judge the living and the dead.

It, moreover, anathematizes, execrates, and condemns every heresy that suggests contrary things. And first it condemns Ebion, Cerinthus, Marcion, Paul of Samosata, Photinus, and all similar blasphemers, who, being unable to accept the personal union of humanity with the Word, denied that our Lord Jesus Christ was true God, proclaiming Him pure man who was called divine man by reason of a greater participation in divine grace, which He had received by merit of a more holy life. It anathematizes also Manichaeus with his followers, who, thinking vainly that the Son of God had assumed not a true but an ephemeral body, entirely do away with the truth of the humanity in Christ. And also Valentinus who asserts that the Son of God took nothing from the Virgin Mary, but assumed a heavenly body and passed through the womb of the Virgin just as water flows and runs through an aqueduct. Arius also, who asserted that the body assumed from the Virgin lacked a soul, and would have the Godhead in place of the soul. Also Apollinaris, who, understanding that there was no true humanity if in Christ the soul is denied as giving the body form, posited only a sensitive soul, but held that the Godhead of the Word took the place of a rational soul. It also anathematizes Theodore of Mopsuestia and Nestorius who assert that humanity was united with the Son of God through grace, and hence there are two persons in Christ, just as they confess that there are two natures, since they were unable to understand that the union of humanity with the Word was hypostatic, and so refused to accept the subsistence of God. For according to this blasphemy, the Word was not made flesh, but the Word through grace lived in the flesh; that is, He was made not the Son of God, but rather the Son of God lived in man. It anathematizes also, execrates, and condemns Eutyches the archimandrite; since he believed according to the blasphemy of Nestorius that the truth of the Incarnation is excluded, and therefore it is fitting that humanity was so united to the Word of God that the person of the Godhead and of humanity were one and the same and also, he could not grasp the unity of person as long as a plurality of natures existed, just as he established that there was one person of the Godhead and humanity in Christ, so he asserted that there was one nature, meaning that before the union there was a duality of natures, but in the assumption they passed over into one nature, with the greatest blasphemy and impiety granting either that humanity was turned into Godhead, or Godhead into humanity. It also anathematizes, execrates, and condemns Macarius of Antioch and all who hold similar views; although he had a correct understanding of the duality of natures and the unity of person, yet he erred greatly concerning the operations of Christ when he said that in Christ there was one operation and one will on the part of both natures. All these, together with their heresies, the Holy Roman Church anathematizes, affirming that there are two wills and two operations in Christ.

It firmly believes, professes, and teaches that no one conceived of man and woman was ever freed of the domination of the Devil, except through the merit of the mediator between God and men, our Lord Jesus Christ; He who was conceived without sin, was born and died, through His death alone laid low the enemy of the human race by destroying our sins, and opened the entrance to the kingdom of heaven, which the first man by his own sin had lost with all succession; and that He would come sometime, all the sacred rites of the Old Testament, sacrifices, sacraments, and ceremonies disclosed.

It firmly believes, professes, and teaches that the matter pertaining to the law of the Old Testament, of the Mosaic law, which are divided into ceremonies, sacred rites, sacrifices, and sacraments, because they were established to signify something in the future, although they were suited to the divine worship at that time, after our Lord’s coming had been signified by them, ceased, and the sacraments of the New Testament began; and that whoever, even after the passion, placed hope in these matters of the law and submitted himself to them as necessary for salvation, as if faith in Christ could not save without them, sinned mortally. Yet it does not deny that after the passion of Christ up to the promulgation of the Gospel they could have been observed until they were believed to be in no way necessary for salvation; but after the promulgation of the Gospel it asserts that they cannot be observed without the loss of eternal salvation. All, therefore, who after that time observe circuмcision and the Sabbath and the other requirements of the law, it declares alien to the Christian faith and not in the least fit to participate in eternal salvation, unless someday they recover from these errors. Therefore, it commands all who glory in the name of Christian, at whatever time, before or after baptism, to cease entirely from circuмcision, since, whether or not one places hope in it, it cannot be observed at all without the loss of eternal salvation. Regarding children, indeed, because of danger of death, which can often take place, when no help can be brought to them by another remedy than through the sacrament of baptism, through which they are snatched from the domination of the Devil and adopted among the sons of God, it advises that holy baptism ought not to be deferred for forty or eighty days, or any time according to the observance of certain people, but it should be conferred as soon as it can be done conveniently, but so, that, when danger of death is imminent, they be baptized in the form of the Church, early without delay, even by a layman or woman, if a priest should be lacking, just as is contained more fully in the decree of the Armenians...

We already have a dogmatic definition regarding this.
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How does this novelty square with the ex-cathedra Catate Domino?
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It (the Holy Roman Catholic Church) firmly believes, professes, and proclaims that those not living within the Catholic Church, not only pagans, but also Jєωs and heretics and schismatics cannot become participants in eternal life, but will depart “into everlasting fire which was prepared for the devil and his angels” [Matt. 25:41], unless before the end of life the same have been added to the flock; and that the unity of the ecclesiastical body is so strong that only to those remaining in it are the sacraments of the Church of benefit for salvation, and do fastings, almsgiving, and other functions of piety and exercises of Christian service produce eternal reward, and that no one, whatever almsgiving he has practiced, even if he has shed blood for the name of Christ, can be saved, unless he has remained in the bosom and unity of the Catholic Church. -Papal Bull of Pope Eugene IV
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