天人合一的「天」主要體現出一種人文精神，而神人合一的前提是相信神的救贖而非自我道德拯救。雖然，「天人關係」與「神人關係」的變化，都在於人類的一種超越自我的傾向和終極的關懷，但天人合一最終從神本走向人本、從天道走向人道，而神人合一本來自於神的計畫，最終也因著耶穌再次歸向神。宗教大同的實現，需要超越性的大愛。

In Chinese philosophy, the Heaven (Tien) in the “Tienrenheyi” is moral and human oriental. But in the Bible, the “Union Mystical” is hypostatic (the Holy Father, Holy Son and Holy Spirit) and the God inside is who he is. So, there are two different approaches: one towards the humanity and the other to the Almighty Creator: who is, who was and who is to come. The harmony of religions does need the transcendent love.