The notion of an indulgence is arguably the most misunderstood aspect of Catholic belief, even among faithful Catholics. The misunderstanding stems from a lack of awareness of what is identified as the double consequence of sin. 

Every sin entails two consequences: Either eternal punishment that is only remitted by Confession and absolution or temporal punishment that constitutes an unhealthy attachment to creation that every sin fosters. This latter punishment God inflicts for sin, even after they have been forgiven. Termporal punishment also requires purification and it can take place either on earth or in purgatory. 

The Catechism of the Catholic Church describes it this way, “To understand this doctrine and practice of the Church, it is necessary to understand that sin has a double consequence. Grave sin deprives us of communion with God and therefore makes us incapable of eternal life, the privation of which is called the "eternal punishment" of sin. On the other hand every sin, even venial, entails an unhealthy attachment to creatures, which must be purified either here on earth, or after death in the state called Purgatory. This purification frees one from what is called the "temporal punishment" of sin” (CCC, n. 1472). 

For older Catholics, prior to the changes instituted after Vatican II, before the apostolic constitution revising the practice of indulgences, various prayers had indulgences attached to them and, by offering those prayers the indulgenced activity had ascribed to it a certain terms of days or years relieved from time in purgatory. Those numerical amounts were derived from the Church’s penitential canons that ascribed the number of days of penance required for various sins committed – e.g. 100 days, 7 years and so forth. 

Receiving an indulgence is not the same as being granted forgiveness. Only God can forgive sins and that is guaranteed in the Sacrament of Penance, in humbly confessing the sins committed to a priest, receiving absolution for them, and fulfilling the prescribed penance. 

An indulgence is not a substitute for confession, but applies to already forgiven sins that entail temporal punishment, after having been absolved of sins committed. Illustrating a contrite heart for sins committed, the residual effect of an undue attraction to sinning remains and must be accounted for, whether by indulgenced acts of charity or mercy or consigned to doing so in Purgatory. 

In the decree Indulgentiarum octrina, Norm 1, Pope Paul VI provided this definition of indulgence, “An indulgence is a remission before God of the temporal punishment due to sins whose guilt has already been forgiven, which the faithful Christian who is duly disposed gains under certain defined conditions through the Church's help when, as a minister of Redemption, she dispenses and applies with authority the treasury of the satisfactions won by Christ and the saints.” That same document, in simplifying the process of obtaining an indulgence, eliminated the time measurements for partial indulgences and in Norm 4 labeled those indulgences as partial. The second type of indulgence is plenary or total freedom from the temporary punishment due to sin.

Obtaining The Plenary Indulgence during the Holy Year

 
This is “a Jubilee grace’ which ‘allows us to discover how limitless God's mercy is.”   Pope Francis
 
The indulgence, a priceless gift of divine mercy, is one of the special ‘signs’ of the Jubilee Year. On May 13, 2024,  the Apostolic Penitentiary published the Norms on the granting of Indulgences during the Jubilee of 2025. The indulgence, they state, (quoting Pope Francis in the Bull of Indiction of the Jubilee, Spes non confundit), is ‘a Jubilee grace’ which ‘allows us to discover how limitless God's mercy is.’ For the next Jubilee, at the express wish of the Holy Father, the Penitentiary intends to ‘nourish the pious desire to obtain the indulgence’ and for this reason it has established norms and guidelines for pilgrims.
 
All the ‘truly repentant’ faithful, ’moved by a spirit of charity, who, purified through the sacrament of penance and refreshed by Holy Communion, will be able to receive the indulgence, with the remission and forgiveness of sins’ say the Norms adding that they should also pray according to the intentions of the Supreme Pontiff. Following the provisions of the Penitentiary, signed by the Major Penitentiary, His Eminence, Cardinal Angelo De Donatis, the indulgence can be applied ‘in the form of suffrage to the souls in Purgatory’.
 
The faithful, ‘pilgrims of hope’, will be able to obtain the Indulgence by undertaking a pilgrimage to any sacred Jubilee site, to at least one of the four Major Papal Basilicas of Rome, to the Holy Land or to other designated ecclesiastical sites, and taking part in a moment of prayer, a liturgical celebration or celebrating the sacrament of reconciliation. The indulgence can also be obtained by ‘devoutly visiting any Jubilee site’ and taking part in Eucharistic adoration or meditation, concluding with the Our Father, the Profession of Faith, and appropriate invocations to Mary.
 
In the event of serious impediments, the truly repentant faithful unable to participate in the celebrations, pilgrimages or visits will be able to obtain the Jubilee indulgence under the same conditions if they recite in their own home or from wherever they are impeded from travelling, the Our Father, the Profession of Faith in any legitimate form and other prayers compliant with the purposes of the Holy Year, offering up their sufferings or the hardships of their lives.
 
For those who cannot travel
Another way to obtain indulgence will be through ‘works of mercy and penance’, with which a person’s conversion is manifested. The faithful ‘following the example and mandate of Christ’, are encouraged to carry out works of charity or mercy more frequently, mainly in the service of those brothers and sisters who are burdened by various needs. Likewise, they may obtain the indulgence by visiting those ‘who are in need or difficulty (the sick, prisoners, the lonely elderly, the disabled...), ‘in a sense making a pilgrimage to Christ present in them.’
 
The ‘penitential spirit’, notes the Norms, is ‘the soul of the Jubilee’ and therefore the indulgence can also be obtained by ‘abstaining, in a spirit of penance, at least for one day of the week from futile distractions (real but also virtual distractions), from superfluous consumption as well as by donating a proportionate sum of money to the poor; by supporting works of a religious or social nature, especially in support of the defense and protection of life in all its phases.’
 
Excerpted from iubilaeum2025.va, the official website of the International Jubilee of Hope 2025.