"I will instruct thee and teach thee in the way which thou shalt go: I will guide thee with mine eye." Psalm 32:8
"Wait on the Lord: be of good courage, and He shall strengthen thine heart: wait, I say, on The Lord." Psalm 27: 14
"The Lord is My strength and My shield; My heart trusted in Him, and I am helped: therefore My heart greatly rejoiceth; and with my song will I praise Him." Psalm 28:7
It is hard to just pick one Psalm...thank you for asking:) What is yours?