ISB ~ Matthew 13 v35

by the prophet:A reference to Ps 78:2, attributed to Asaph. In 2 Chron 29:30 of the Greek OT, Asaph is called a “prophet”. In any case, all OT writers were inspired by the Spirit and thus prophets (cf. 22:43; 2 Pet 1:20-21).

what has been hidden:Psalm 78:2 accents the positive function of parables: they enlighten the humble by revealing God’s mysteries.

See word study:Parables.