BSO guest conductor Rafael Frühbeck de Burgos has developed a special relationship with John Oliver and his Tanglewood Festival Chorus over the past several seasons. This was very much in evidence in the Orchestra’s concert on March 20, beginning with a podcast on the BSO’s web site in which Frühbeck de Burgos and Oliver talked about the oncoming program and several other delectable things between two like-minded musicians. The Spanish maestro, revealing his great admiration for the chorus, praised its remarkable flexibility in rehearsal and performance. And anyone with a pair of ears and eyes who has attended the earlier collaborations between the conductor and this chorus has certainly heard and seen this in concert. There has always seemed to be a great affection in the chorus’s responses to Frühbeck de Burgos as they traversed much of the choral repertoire from Carmina Burana through the Beethoven Ninth Symphony. Their completely riveting contributions de Falla’s La Vide Breve still happily haunt the memory.

Last week’s concerts were to have been the last TFC/F. de B. collaborations this season, so perhaps the extra sense of frisson heard in the Rossini Stabat Mater could be attributed to an affectionate sense of farewell from the chorus to the conductor, but he had the willing and committed performances of the BSO members and a superb quartet of vocal soloists along with him as well. I am not exaggerating in saying that this unusual and rarely performed Rossini “oratorio,” as Frühbeck de Burgos had described it, received a performance that one could not have imagined as being any better.

This unusual 10-movement work, whose poetry describes the anguish of Jesus’ mother as she views his crucifixion, went from strength to strength from its very first notes, and what one immediately noticed was Frühbeck de Burgos’s total command of every nuance and his total ease in demonstrating exactly what he wanted to hear from everyone on stage. He had noted earlier that he has performed this work all over Europe, and to great acclaim. It was clear that he had worked through all of the many challenges of tempi, mood and balance the piece presents. In the hands of a lesser musician, parts of this work can stray into tawdriness and almost amusing musical “second-class-ness.” Not for one second did this happen in these performances. What emerged was a remarkable work of great emotion and a very Italianate passion. Not only is this a work of great originality, it also presages music to come. One regularly heard foreshadowing of what Verdi would later employ, especially in his Manzoni Requiem.

The Tanglewood Festival Chorus was clearly the hero of the evening whenever it sang. This was surely one of that organization’s most fully satisfying performances. It was clear from the very first movement when they sang the dramatically set and halting text “dum – pen – de – bant fi – li – us” (where her Son was hanging), with perfectly centered and rich yet text-aware tone, that we were in for a special evening of choral singing.

Tenor Eric Cutler sang the “Cujus animam” aria with a pleasing, bright Italianate tone, disappointing only at the end when he somewhat hammily shut his score and physically assumed the posture of an affected soloist about to reach for a high c-sharp, which on Saturday was something of a stretch for him.  He was admittedly quite good, musically, but off-putting visually in this, his “big moment.”

“Quis es Homo” is scored for chorus and mezzo-soprano was notable for its fabulous singing from Alice Coote, who brought an almost Kathleen Ferrier-like richness of focus and tone to her music, and the elegant pacing and playing brought by the conductor and the orchestra.

Bass soloist Alfred Walker and the chorus rose splendidly to the occasion of Rossini’s a cappella setting of the “Eia, mater” text, which Frühbeck de Burgos elected to conduct without baton. Hearing the chorus correct the sometimes not-quite-perfect tuning of Mr. Walker in this treacherous little movement was instructive and heartening. The conductor artfully led the ensuing “Sancta mater” with wonderfully controlled rubati and dynamics. The give-and-take here was of the highest order that one longs to hear but so rarely does.

Ms. Coote returned for her gorgeous “Fac ut portem” aria and one was once again moved by her creamy tone put to the service of precise rhythm, textural clarity and dynamic control. This is one very communicative singer. Yet any mezzo who sings this aria knows that however beautifully she may sing, she will soon be overshadowed by the next movement, the ultra-dramatic soprano–and-chorus “Inflammatus.”

Here was soprano Albina Shagimuratova’s chance to shine, and shine she did, super-nova style, with brilliant tone and fabulous focus. Yet, she was up against an almost superhuman rival for attention. It must be said that the Tanglewood Festival Chorus, when singing in unison and asked for fortisissimo, as they were several times on the text “…in die judicii” (on the day of judgment) was truly something to behold, a veritable force of nature. I can’t recall hearing such appropriately laser-focused sound from a chorus ever before. It was absolutely stunning, and yet, so was the rapt and dramatic singing they brought to the soft music that followed. TFC actually surpassed the soloist in this movement – quite an achievement in this molto drammatico environment!

The a cappella “Quando corpus morietur” chorus which followed was sung dead-in-tune from its beginning to its end, further evidence of the TFC’s all-around mastery of the challenges presented by this work. One again eschewing the baton, de Burgos shaped the chorus’s sinuous musical lines as might a sculptor his marble. The TFC’s rapt and sensitive tone and its attention to his every gesture made believers of everyone in the hall.

Rossini sets his final movement “In sempiterna secula, Amen” as an instrumental and choral fugue, and Frühbeck de Burgos took special pains to ensure that its many overlapping sequential entrances were clear and never covered by the complicated counterpoint. Near the movement’s end Rossini, always the dramatic showman, stops the fugue in its tracks and poignantly recalls the spare and foreboding music that was first heard at the very beginning the Stabat Mater’s first movement. The fugue then begins anew where it left off and brings this remarkable music to an emphatic close.

As the soloists walked onstage for their bows, the chorus’s conductor, John Oliver, joined them. When he gestured to chorus to stand for its bow, well-deserved and very well focused bravos welled up from the audience. They knew what they had just heard, and so did Mr. Oliver. His smile spoke volumes. And, similar bravos were accorded Frühbeck de Burgos and the orchestra for their significant contributions to this evening of extraordinary music making.

The concert had begun with a somewhat generic traversal of the music from Mendelssohn’s magical Overture and Incidental Music written for Shakespeare’s A Midsummer Night’s Dream. The orchestra’s Principal Flautist Elizabeth Rowe was calm, collected and lovely in her daunting solo in the Scherzo, as were indeed all of the woodwinds. Associate Principal Horn Richard Sebring was nonpareil in his Nocturne solo, and Mss. Shagimuratova and Coote were spot-on in their solos. The women of the Tanglewood Festival Chorus were a somewhat large yet elegant and fleet-voiced gathering of fairies. Maestro Frühbeck de Burgos kept things moving right along.

John W. Ehrlich is music director of Spectrum Singers, which he founded 29 years ago. He has been a singer and conductor in the Boston area for more than 30 years.