The Holy Spirit is no Skeptic, & the things He has written in our hearts are not doubts or opinions, but assertions - surer & more certain than sense & life itself.
When one is possessed with doubt, that though he call upon the Lord he cannot be heard, and that God has turned him heart from him, and is angry ... he must arm himself with God's Word, promising to hear him.
The Holy Spirit is no skeptic. He has written neither doubt nor mere opinion into our hearts, but rather solid assurances, which are more sure and solid than all experience and even life itself.