(The following text is taken from the decree of the 23rd Session of the Ecumenical Council of Basel, promulgated on 26 March 1436 under the authority of Pope Eugene IV. It is noteworthy primarily for the text of the Pope's oath, by which he consents to receive his office, and the explanation of how he can best fulfill it. This decree has since been superseded by other practices surrounding the election of the popes, and certainly today there is no promise that the elected pontiff will abide by the decrees of Basel regarding the holding of ecumenical councils, which were disastrously imprudent. But the core of the promise, and the subsequent discussion of it, are both very interesting.)
26 March 1436
The holy synod decrees that the person elected as pope is obliged to express his consent to the election in the manner stated below. [...] After he has been informed of the election, he is bound to act within a day of the demand. If he does not do so, his election is annulled and the cardinals must proceed in the Lord's name to another election. But if he expresses his consent, as stated above, the cardinals shall straightaway make due obeisance to him as supreme pontiff. Once the obeisance has been made by the cardinals, nobody has any right to challenge his pontificate.
[The Pope's Oath of Consent]
In the name of the holy and undivided Trinity, Father, Son and holy Spirit. I, N. , elected pope, with both heart and mouth confess and profess to almighty God, whose church I undertake with his assistance to govern, and to blessed Peter, prince of the apostles, that as long as I am in this fragile life I will firmly believe and hold the catholic faith, according to the tradition of the apostles, of general councils and of other holy fathers, especially of the eight holy universal councils — namely the first at Nicaea, the second at Constantinople, the third which was the first at Ephesus, the fourth at Chalcedon, the fifth and sixth at Constantinople, the seventh at Nicaea and the eighth at Constantinople — as well as of the general councils at the Lateran, Lyons, Vienne, Constance and Basel, and to preserve intact this faith unchanged to the last dot, and to defend and preach it to the point of death and the shedding of my blood, and likewise to follow and observe in every way the rite handed down of the ecclesiastical sacraments of the church. I promise also to labour faithfully for the defense of the catholic faith, the extirpation of heresies and errors, the reform of morals and the peace of the Christian people. I swear also to continue with the holding of general councils and the confirmation of elections in accordance with the decrees of the holy council of Basel. I have signed this profession with my own hand; I offer it on the altar with a sincere mind to you almighty God, to whom on the day of tremendous judgment I shall have to give an account of this and all my deeds; and I will repeat it at the first public consistory.
[Requirements Surrounding this Oath]
So that this salutary institution may not fade from the supreme pontiff's memory with the passage of time, every year on the anniversary of his election or of his coronation, the first cardinal present shall, during mass, publicly and in a loud voice address the supreme pontiff thus: "Most holy father, may your holiness heed and carefully ponder the promise which you made to God on the day of your election." He shall then read out the promise and shall continue as follows: May your holiness, therefore, for the honor of God, for the salvation of your soul and for the good of the universal church, strive to observe to your utmost all these things in good faith and without guile or fraud.
Recall whose place it is that you hold on earth, namely of him who laid down his life for his sheep, who thrice asked the blessed Peter if he loved him, before he entrusted his sheep to him', and who, as the just judge whom nothing secret escapes, will exact from you an account of everything to the very last farthing. Remember what blessed Peter and his successors as pontiffs did: they thought only of the honor of God, the spread of the faith, the public good of the church and the salvation and benefit of the faithful; finally, imitating their master and Lord they did not hesitate to lay down their lives for the sheep entrusted to them.
Do not lay up for yourself or your kinsfolk treasures on earth, where moth and rust consume and where thieves and robbers break in, but lay up for yourself treasure in heaven. Do not be an acceptor of persons or of blood-ties or of homeland or of nation. All people are children of God and have been equally entrusted to your care and safe-keeping. Say after the example of Christ: Whoever does the will of my Father in heaven, he is my brother and sister and mother. In distributing dignities and benefices put before yourself neither the flesh nor gifts nor anything temporal at all, but solely God and the virtues and merits of people. Exercise ecclesiastical discipline in correcting faults, mindful of what grace Phinehas merited and what punishment Eli, the one for avenging injuries to God, the other for pretending not to know them. Defend, help and support the poor and needy. Show a fatherly charity to all.
After the solemnities of his coronation, and each year after the anniversary of his election, the supreme pontiff shall carefully discuss with his brethren, for at least eight consecutive days, how he shall carry out his solemn promises to God. In the first place, therefore, he should examine where in the world the Christian religion is being persecuted by Turks, Saracens, Tartars and other infidels; where heresy or schism or any form of superstition flourishes, in which provinces there has been a decline in morals and observance of the divine precepts and in the right way of living, in both ecclesiastical and secular matters, where ecclesiastical liberty is infringed; among which kings, princes and peoples enmity, wars and fears of war are rife; and like a dutiful father he should strive with his brethren carefully to provide remedies.
When these affairs of an universal character have been settled, let him deal with those nearer at hand. Let him begin by reforming and ordering in an exemplary way his house, his household and the Roman curia, where and in so far as this is necessary, so that from the visible reform of the church which is the head of all others, lesser churches may draw purity of morals and no occasion may be given for calumny and malicious talk. Making diligent inquiry in person and through others about both important and lesser persons, he should allow no delay or pretence in correcting whatever is found in need of reform, remembering that the sin is twofold, the one being committed, the other and far more serious being its consequences. For whatever is done there is easily made into an example. That is why, if the head is sick, disease enters into the rest of the body. The papal household and court should be a kind of clear mirror, so that all who look at it form themselves and live according to its example. Thereafter let him banish and eradicate any traces of simony, filthy concubinage or whatever may offend God or scandalize people.
He should take care that officials do not exercise their offices badly or oppress anybody or extort anything by threats or illegal means, and that those in charge of the officials do not let their excesses go unpunished. They should not tolerate clothes and colours which are forbidden by the sacred canons. Let him instruct the Roman clergy, who are chiefly and immediately subject to him, in all ecclesiastical decorum, admonishing them that God's approval depends not on the parade and splendour of clothes but on humility, docility, purity of mind, simplicity of heart, holiness of behaviour and the other virtues which commend their possessor to God and to people. Let him enact reforms especially so that the divine services may be observed in the churches of Rome with all seemly devotion and discipline. He should also instruct the people of Rome, which is his own parish, and direct them in the way of salvation. He should bid the cardinals to visit and reform their titular churches and parishes as befits their office. He should appoint some prelate of great learning and of proven and exemplary life as his vicar in the city, to take his place in the episcopal care of the clergy and people, and he should often inquire about whether he is fulfilling his task.
The supreme pontiff calls himself the servant of the servants of God; let him prove it in deeds. As long as people from all parts have recourse to him as to a common father, he should give them all easy access. Let him set aside at least one day in the week for a public audience, when he shall listen with patience and kindness to all, especially the poor and oppressed, and shall grant their prayers as much as he can with God's help, and shall assist all with kind advice and help as each one has need and as a father does for his children. If he is prevented by some bodily need, he shall entrust this task to some cardinal or other noteworthy person who will report everything to him, and he shall order all officials of the curia, especially the vice-chancellor, the penitentiary and the chamberlain, to expedite business for the poor with speed and free of charge, bearing in mind the apostolic charity of Peter and Paul, who pledged themselves to remember the poor.