en_tn/1ki/08/38.md

prayers and humble requests

The words "prayer" and "humble requests" mean basically the same thing and emphasize that the person is sincere as he makes his request. See how you translated similar words in 1 Kings 8:28. Alternate translation: "requests" (See: rc://en/ta/man/jit/figs-doublet)

knowing the plague in his own heart

Possible meanings are 1) The person's sin is spoken of as if it were a plague. Alternate translation: "knowing the sin in his own heart" or 2) The "plague" is a metonym for the sins that the disasters are a punishment for. Alternate translation: "knowing in his heart that the plague is the result of his own sin" (See: rc://en/ta/man/jit/figs-metaphor and rc://en/ta/man/jit/figs-metonymy)