In repentance and rest is your salvation, in quietness and trust is your strength.
The Lord is my strength and my song; he has become my salvation.
...the joy of the Lord is your strength
The Lord is my strength and my shield; my heart trusts in him, and I am helped. My heart leaps for joy and I will give thanks to him in song. The Lord is the strength of his people, a fortress of salvation for his anointed one.