'Weakness' in the Bible

My sojourning hath departed, And been removed from me as a shepherd's tent, I have drawn together, as a weaver, my life, By weakness it cutteth me off, From day unto night Thou dost end me.

To appoint to mourners in Zion, To give to them beauty instead of ashes, The oil of joy instead of mourning, A covering of praise for a spirit of weakness, And He is calling to them, 'Trees of righteousness, The planting of Jehovah -- to be beautified.'