Discovery Box1 Corinthians 14:4 
Context14:4 The one who speaks in a tongue builds himself up, 1 but the one who prophesies builds up the church.
1 Corinthians 14:21-22
Context14:21 It is written in the law: “By people with strange tongues and by the lips of strangers I will speak to this people, yet not even in this way will they listen to me,” 2 says the Lord. 14:22 So then, tongues are a sign not for believers but for unbelievers. Prophecy, however, is not for unbelievers but for believers.
1 sn The Greek term builds (himself) up does not necessarily bear positive connotations in this context.
2 sn A quotation from Isa 28:11-12.
