Billboard stated that "Nightingale" is a return to her earlier style compared to her previous single "Jazzman" and has "fine soft melodies set off by her distinctive vocalizing.

"[2] Cash Box said that the "solid hook cements the powerful combination of sharp lyrics and catchy musical feel.

"[3] Record World said that it "combines melodic beauty with momentum extraordinaire to come up with a performance in super league with [King's] recent chart-topper 'Jazzman.

'"[4] The song is a critical part of the plot in "The Night Bird", a psychological suspense novel by Brian Freeman.

In the novel, the song is used as a trigger to awaken hypnotically suppressed phobias in psychiatric patients, causing them to commit suicide.