This article analyses Paul’s use of δοκιμάζειν in 1 Thessalonians 5:21 within the context of verbs for discernment (δοκιμάζειν, πειράζειν, διακρίνειν and their cognates). It discusses Paul’s use of these verbs against the background of discernment in the Septuaginta. Paul’s own understanding of discernment is then further investigated in terms of his socio-religious background and other New Testament books. It shows how he links discernment with a concrete situation and how discernment enables the human heart to realise its full potential by purifying it from all obstacles. It then discusses how the present tense of the imperative δοκιμάζετε in 1 Thessalonians 5:21 points towards the ongoing nature of discerning God’s will and, finally, how Paul’s eschatological context in 1 Thessalonians implies that discernment also has a future dimension.