Life-Giving Spirit
This last statement, ‘the last Adam [became] a life-giving spirit’ (1 Cor. 15:45), is as significant as it is extraordinary. Here the NIV translation may fail us, for ‘spirit’ in this context probably refers to the Holy Spirit, and should be capitalized. Christ on his ascension came into such complete possession of the Spirit who had sustained him throughout his ministry that economically the resurrected Christ and the Spirit are one to us.
Sinclair Ferguson, The Holy Spirit, ed. Gerald Bray, Contours of Christian Theology (Downers Grove, IL: InterVarsity Press, 1996), 54.