An important milestone was the year 1863 – the millennium of the arrival of St. Cyril and Methodius to Great Moravia. The parish priest Július Plošic played a key role in Selce, who from 1854 worked diligently on the restoration of the church and on the elevation of the spiritual and national life of the faithful.

With the support of Bishop Štefan Moyses, he achieved a change in the patronage of the church (making the Selčiansky church the first in Slovakia dedicated to St. Cyril and Methodius) and commissioned the creation of a new altarpiece to the Banská Bystrica painter Július Jonáš.

Its ceremonial consecration, after many difficulties, took place on May 31, 1863, on the feast of the Holy Trinity, and became a great national-ecclesiastical event.

Since early morning, long processions of pilgrims from all over the area had been arriving in Seleccié. When they appeared on the horizon, salvos from mining mortars rang out, thundering through the mountains and announcing the beginning of the celebration. Together with the ringing of bells, they created a powerful soundscape that welcomed the faithful as they entered the village. Bands from surrounding villages also played along with them, accompanying the pilgrims with music. The band of the famous Liptov Primate Jožek Piť attracted particular attention, playing not only the imperial anthem but also Slovak national songs, thus enhancing the festive atmosphere of the entire day. The celebration culminated in a holy mass, during which quartets and a mass by Ján Levoslav Bella, specially composed for this occasion, were performed. Sermons under the open sky were delivered by prominent Slovak nationalists Štefan Závodník and Juraj Slota, who emphasized the legacy of the Thessaloniki brothers for the faith and identity of Slovaks. The grandeur of the celebrations was also underlined by commemorative medals and a large “joy cake” – a huge cake with an anniversary inscription, which was shared by the participants of the celebration.

At the turn of the 19th and 20th centuries, the parish priest František Šujanský continued to develop the parish. In 1894–1895, he had the nave of the church extended and the western tower built, giving the church its current appearance and decorating the interior in the neo-Gothic style. In addition to building interventions, he also devoted himself to shaping the spiritual and national awareness of the faithful.

In the 1980s, the interior of the church underwent significant renovations to adapt the space to the requirements of the new liturgy after the Second Vatican Council. A new altar table was placed in the presbytery and changes also affected part of the original neo-Gothic furnishings. In 1996, the original altarpiece of St. Cyril and Methodius from 1863 was restored and placed again in the sanctuary of the church. Since 1998, Selce has been the diocesan center of veneration for the Thessaloniki brothers, thanks to the Banská Bystrica bishop Rudolf Baláž, which brought about the renewal of regular Cyril-Methodist pilgrimages. The importance of this place was further strengthened by the placement of the relic of St. Cyril in 2013, on the 1150th anniversary of the arrival of the missionaries in Great Moravia.