It is the power to endure. The Holy Spirit gives us both the power of the short distance high speed sprinter, AND the power of endurance of the long distance runner. The Holy Spirit gives us the power, ability or might to perform anything that God requires of us. The Holy Spirit gives us the power to handle difficult situations, or to step out in faith in ways that we never dreamed of before. In addition to power, the Holy Spirit is also a spirit of agape love.
Agape love is pure love.
It is the kind of love that exists between the Father and the Son. It is a love that is deep, constant and true. Paul promises Timothy that through the Holy Spirit he will have all the love he needs to pastor the people of God. He will have a pastor's heart. Finally Paul promises Timothy that instead of a spirit of timidity he will have a Spirit of self discipline.