Genesis 4:12-14

Genesis 4:12-14

[12] When  thou tillest  the ground,  it shall not henceforth  yield  unto thee her strength;  a fugitive  and a vagabond  shalt thou be in the earth.  [13] And Cain  said  unto the LORD,  My punishment  is greater  than I can bear.  [14] Behold, thou hast driven me out  this day  from the face  of the earth;  and from  thy face  shall I be hid;  and I shall be a fugitive  and a vagabond  in the earth;  and it shall come to pass,  that every one that findeth me  shall slay me. 

What is the context of Genesis 4:12-14?