The first edition of Calvin's Genevan Psalters appears in 1551; the work’s music editor is French composer and music theorist Loys (Louis) Bourgeois, to whom scholars attribute the Protestant doxology known as the Old 100th, one of the most famous melodies in all of Christendom.

Beza, at a loss for immediate occupation, had gone to Tübingen to see his former teacher Wolmar.

On his way home he visited Pierre Viret at Lausanne, who brought about his appointment as professor of Greek at the academy there from November, 1549).

Beza has found time to write a Biblical drama, Abraham Sacrifiant, in which he contrasts Catholicism with Protestantism, and the work has been well received.

In June, 1551, he had added a few psalms to the French version of the Psalms begun by the late Clément Marot, which is also very successful.

About the same time, he had published Passavantius, a satire directed against Pierre Lizet, the former president of the Parliament of Paris, and principal originator of the "fiery chamber" (chambre ardente), who, at is at this time abbot of St. Victor near Paris and publishing a number of polemical writings.

Of a more serious character are two controversies in which Beza is involved at this time.

The first concerns the doctrine of predestination and the controversy of Calvin with Jerome Hermes Bolsec.

A sermon which Bolsec had preached at Paris had aroused misgivings in Catholic circles regarding the soundness of his ideas, and Bolsec had left Paris.

Having separated from the Catholic Church about 1545, he had taken refuge at the Court of Renée, duchess of Ferrara, who was favorably disposed towards Protestant views.

Here he had married, and begun the study of medicine, about 1550 settling as a physician at Veigy, near Geneva.

A theological controversy with Calvin, whose doctrine of predestination he deemed an absurdity, soon ensued.

In 1551, at one of the religious conferences or public discussions held at Geneva every Friday, the orator of the day, Jean de Saint André, is speaking on predestination.

Bolsec, after interrupting him and arguing against him, is arrested, and through the influence of the reformer banished from Geneva.

Bolsec will some years later publish negative biographies of Calvin and Beza.