'Weak' in the Bible

Have mercy on me and be gracious to me, O Lord, for I am weak (faint, frail);Heal me, O Lord, for my bones are dismayed and anguished.

Blessed [by God’s grace and compassion] is he who considers the helpless;The Lord will save him in the day of trouble.

He will have compassion on the poor and needy,And he will save the lives of the needy.

Vindicate the weak and fatherless;Do justice and maintain the rights of the afflicted and destitute.

My knees are unsteady from fasting;And my flesh is gaunt and without fatness.