The Papal document, Domus Ecclesiae, spells out the specific privileges granted to a minor basilica. The most important is the Plenary Indulgence which the faithful may receive who devoutly visit the basilica and participate in any sacred rite "or at least recite the Lord's Prayer and the profession of faith." For this reason, we should expect many pilgrims beyond those visitors interested in our art and architecture. Domus Ecclesiae's list of privileges continues:
[With the conditions specified above, Pilgrims at the Basilica of St. Mary of the Angels] may obtain a plenary indulgence under the usual conditions (sacramental confession, Eucharistic Communion, and prayer for the intention of the Supreme Pontiff):
3. The papal symbol, that is, "crossed keys," may be exhibited on banners, on furnishings, and on the seal of the basilica.
Catholic pilgrims generally travel to a basilica to receive a Plenary Indulgence. So what is a Plenary Indulgence?
Sacrament of Penance (Confession) removes the eternal punishment that our sins merit. But, once forgiven, the wounds and effects of our sins remain and block the full action of the Holy Spirit within us. The Church teaches that we must undergo “temporal” punishment either in this life or after death (in Purgatory) to remove the effects of sin (after Sacrament of Penance- Confession) and prepare us for eternal happiness with God in Heaven. Temporal punishment may be removed while we are still on earth by voluntarily uniting our sufferings in this life with those of Christ and by our prayer and acts of charity. Temporal punishment also may be diminished or removed by a partial or plenary indulgence. An indulgence is a favor granted to an individual by the Church— through the merits of Christ— that removes, either partially or completely (plenary), the temporal punishment that remains for sins that have been forgiven. This is a magnanimous grace of Mercy from God.
Keep in mind...Indulgences do not remove sin. That can only happen in the Sacrament of Penance which also removes the eternal punishment that our sins merit. A Plenary Indulgence completely removes the temporal punishment that remains for our sins that have been forgiven.
Catholics in full communion with the Church may obtain a plenary indulgence for themselves or for a soul in purgatory by carrying out in this Basilica an act of devotion (Mass, adoration, Rosary, for example) with sincerity, following conditions set by the Church and be earnestly striving to eliminate all attachment to sin, whether mortal or venial.
Three Conditions for Receiving an Indulgence:
1. Sacramental Confession within 20 days prior or following the day the indulgence is sought
2. Reception of Holy Communion, preferably on the day of your visit to the Basilica
3. Prayer for the intentions of the Holy Father.
Days that that the plenary indulgence can be received at the Basilica of St. Mary of the Angels are listed above.