This article argues that αρραβων in 2 Corinthians (1.22 and 5.5) does not mean ‘down payment’ or ‘first installment’ but ‘pledge’ without any sense of pars pro toto. After showing that the meaning of the word depends on its context, the study goes on to examine the two occurrences of the word, concluding that Paul either appeals to the Spirit as God's pledge for his apostolicity (1.22) or as a pledge for the surety of bodily resurrection (5.5). The common view that αρραβων depicts the Spirit as the present realization of salvation is thus exegetically unfounded.