Ancient musical instruments, formed of metallic plates which were struck together; they produced no melodious sound in themselves (cf. 1 Corinthians 13:1 ) and could only be used with other instruments. 1 Chronicles 15:16,19,28; Ezra 3:10; Psalm 150:51 etc. In Corinthians it is a similitude of one making a show in speaking without love in the heart.