“You shall receive energy from Me after the Holy Spirit has come upon you and you will be my witnesses” (Acts 1:8, paraphrased). Peter’s energy failed as he depended on himself to keep his word to not deny his Lord; ours will too. Weakness is the state of depending on ourselves; strength is depending on the Spirit. The Energy of God runs the universe; that same Energy is available to each of us to live victorious lives. Ask, and He will be given to you.
“If you then, who are evil, know how to give good gifts to your children, how much more will the heavenly Father give the Holy Spirit to those who ask him!” (Luke 11:13 NRSV)
(From “Sonlight for the Soul”, by H. Lamar Smith)