Þurh-leornian

According to the Old English Dictionary:

þurh-leornian

to learn thoroughly :-- Þes Godes wer þurhleoraode (penetravit) þá deóglan þing þǽre godcundnysse, Gr. D. 136, 4. See þurh-féran, and þurh-leóran; II. þurh-leornian