'Double Portion' in the Bible

But the first-born, son of the hated one, he doth acknowledge, to give to him a double portion of all that is found with him, for he is the beginning of his strength; to him is the right of the first-born.

And it cometh to pass, at their passing over, that Elijah hath said unto Elisha, 'Ask, what do I do for thee before I am taken from thee?' and Elisha saith, 'Then let there be, I pray thee, a double portion of thy spirit unto me;'