'Bitterness of My Soul' in the Bible

I also, cannot restrain my mouth, - I must speak, in the anguish of my spirit, I must find utterance, in the bitterness of my soul.

My soul doth loathe my life, - I let loose my complaint, I speak, in the bitterness of my soul.

What can I say? Since he hath promised for me, Himself, will perform. I will go softly, all my years. Because of the bitterness of my soul,