[Not in your own strength] for it is God Who is all the while effectually at work in you [energizing and creating in you the power and desire], both to will and to work for His good pleasure and satisfaction and delight.
No unbelief or distrust made him waver (doubtingly question) concerning the promise of God, but he grew strong and was empowered by faith as he gave praise and glory to God.
However, I consider my life worth nothing to me, if only I may finish the race and complete the task the Lord Jesus has given me—the task of testifying to the gospel of God's grace.
And I will ask the Father, and He will give you another Comforter (Counselor, Helper, Intercessor, Advocate, Strengthener, and Standby), that He may remain with you forever--
He alone is my rock and my salvation; he is my fortress, I will never be shaken.
Be strong and courageous. Do not be afraid or terrified because of them, for the LORD your God goes with you; he will never leave you nor forsake you.
Never lag in zeal and in earnest endeavor; be aglow and burning with the Spirit, serving the Lord. Romans 12:11