[2] In 1624, he became a choir boy at the Ducal Palace of Vila Viçosa, the ancestral seat of the Dukes of Braganza, while his older brother, Father Marcos Soares Pereira (?-1655) was admitted as chaplain-singer.

[3] In keeping with the aristocratic patterns of behavior of the 17th century, and as a sign of pre-eminence,[4] Teodósio II, the 7th Duke of Braganza (1568-1630) had created an academy for court musicians, the Colégio dos Santos Reis Magos (College of the Three Wise Kings), where Rebelo studied under Robert Turner (c.1578-1629), an Irish musician who himself had been a student of the Flemish composer Géry de Ghersem, and mestre de capela of the ducal chapel from 1616,[5] and possibly also under Friar Manuel Cardoso,[3] one of the most famous and influential Portuguese composers of the time.

This monograph written in Defense of the Modern Composition and Composers is dedicated to you, (…) having seen the book of your four, five, and six-part masses; the music for ten, twelve, seventeen and twenty voices (…) and if they have not yet been published it is not because they fear the light but because they have not been given to it; but they will appear in due course.

[8] In the case of the letter to the Portuguese agent in Rome, dating from March 1654, the King wrote: “I have prepared some books for the press [containing] a complete series of vesper psalms, and other pieces for different choirs and voices by Juan Lourenço Rabelo (…)”.

[3] Choosing a Roman printer can be interpreted as a means of bringing pressure to bear on the Papal States, which still had not recognized Portugal's independence from Spain.

In its abstract architectural quality, inclined more to ignore than to underline the text, in the sound effects ranging from massive to transparent, erected in a diversified play of frequently asymmetrical combinations of voices and instruments, in the demanding instrumental writings and the vocal ornamentation, it leans more to the style of 17th-century northern Italian composers to whose works Rebelo had had privileged access in the rich musical library belonging to King João IV.

At the same time Rebelo knows how to evoke the Roman School polyphony, like is in seven-part motet Panis angelicus, full of harmonic false relations or in his Lamentationes, in which the composer achieves effects through the use of piercing chromatic harmonies.

We may consider the hypothesis of private musical sessions, only with the king attending but, again, the absence of documentary evidence in this matter, refers us to the field of assumptions.

Probably, most of Rebelo's compositions were made in a theoretical and aesthetic sense, looking for a particular style or concept of music more than the display of contrapuntal virtuosity or secure a place in History.