Collaborating as a duo, rapper Talib Kweli and DJ and hip hop producer Hi-Tek recorded the album during 1999 to 2000, following their individual musical work that gained notice in New York's underground scene during the late 1990s.

"[5] AllMusic's Matt Conaway compared Reflection Eternal's music to the work of the Native Tongues collective, while writing that the album "houses enough merit to establish Talib as one of this generation's most poetic MCs".

[14] Kathryn Farr of Rolling Stone called Train of Thought "the rare socially aware hip-hop record that can get fists pumping in a rowdy nightclub".

[10] Noah Callahan-Bever of Vibe shared a similar sentiment, writing "Reflection Eternal's great weakness is Kweli's excessive preaching about the state of hip hop, but at least he cares".

[2] In The New Rolling Stone Album Guide (2004), Jon Caramanica called it "thick with fierce street raps ('Down for the Count' and 'Ghetto Afterlife'), maudlin soul ('Love Language'), and the type of insightful versifying Kweli has made his stock-in-trade ('Memories Live' and 'This Means You')".