The Requiem in D minor, a setting of the Missa pro defunctis for mixed choir, vocal soloists, three trombones, one horn, strings and organ with figured bass,[1] was composed by Bruckner in memory of Franz Sailer, the notary of the St. Florian Monastery, who bequeathed Bruckner a Bösendorfer piano.

"[5] "[It] is amazing what he achieved, especially if we look at the great double fugue of the Quam olim Abrahae, written at least six years before he even commenced his thorough contrapuntal studies with Simon Sechter!

[When reviewing it in 1892,] as a highly self-critical seventy-year-old, Bruckner passed judgement on the work as follows: Es is' net schlecht!

[There] are many passages reminiscent of what was even then, in 1848/49, a past age (the very opening points irresistibly to Mozart's Requiem in the same key), and though the very inclusion of a figured bass for organ continuo strikes one as backward looking, there are already several flashes of the later, great Bruckner to come.

[6][Despite it] is by no means a perfect masterpiece... [it] can be said to be the first full demonstration that the young man was a composer of inestimable promise.

Bayer performed the revised work on 4 December 1895 in Steyr for the funerals of the parish priest Johann Evangelist Aichinger.