He said to Amnon, “Why are you, the king’s son, so depressed morning after morning? Will you not tell me?” And Amnon said to him, “I am in love with Tamar, my [half-] brother Absalom’s sister.”

I chirp like a swallow or a crane;
I moan like a dove.
My eyes grow weak looking upward.
Lord, I am oppressed; support me.

Leah’s eyes were weak, but Rachel was beautiful in form and appearance.

since you are looking for proof that Christ is speaking through me. Christ is not weak in His dealing with you, but is powerful among you. [Note: Paul probably refers to the positive effects of his ministry there in Corinth].