Learning by rote means repeating words or religious practices mechanically, without sincere understanding or devotion. Isaiah uses the idea to expose worship that honors God only outwardly.
Definition
To learn by rote is to repeat words or perform religious service mechanically. The expression describes formal observance without the corresponding inward devotion or genuine understanding.
Biblical Usage
Isaiah 29:13 uses the idea to describe a people whose service of the Lord had become merely formal.
Historical Bible Dictionaries
International Standard Bible Encyclopedia (ISBE)
<p>rot: the Revised Version margin gives "learned by rote" in Isa 29:13 for the King James Version "taught," which indicates that the service of Yahweh was merely formal.</p>