'Loins' in the Bible

but thou dost not build the house, for thy son who cometh forth out from thy loins, he doth build the house for My name.

And the lads who have grown up with him, speak with him, saying, 'Thus dost thou say to the people who have spoken unto thee, saying, Thy father made our yoke heavy, and thou, make light somewhat of our yoke; thus dost thou say unto them, My little finger is thicker than the loins of my father;