Mr Say, 42, who has performed with major orchestras around the world in places including New York, Berlin and Tokyo, said during earlier hearings that the accusations against him went "against universal human rights and laws." The sentence was suspended for five years, meaning that the pianist will not be sent to prison unless he is convicted of re-offending within that period.
In recent years, many intellectuals, writers and artists have been prosecuted for statements about Islam and Turkish identity, both of which the pro-Islamic government seeks to shield from criticism. Social media outlets like Facebook and Twitter, however, have rarely figured in previous trials, although Turks are active users of the sites.
The messages cited in the indictment were Mr Say's remarks referring to a poem by a famous 11th-century Persian poet, Omar Khayyam, which poked fun at an Islamic vision of the afterlife.