Since the beginning of time God has given us agency; our first choice was to choose whether we wanted to come down to the Earth and gain a body or to live with Satan and never receive a body. God created opposition in all things so we can learn and grow and be able to choose which path we want to follow. In the Book of Mormon in the book of 2 Nephi 2:15-16 it says, "And to bring about his eternal purposes in the end of man, after he had created our first parents, and the beasts of the field and the fowls of the air, and in fine, all things which are created, it must needs be that there was an opposition; even the forbidden fruit in opposition to the tree of life; the one being sweet and the other bitter.
Wherefore, the Lord God gave unto man that he should act for himself. Wherefore, man could not act for himself save it should be that he was enticed by the one or the other." Since the beginning of time God has given us the choice to choose good from evil, right from wrong, and to follow him or follow satan. God has promised us that if we choose to follow him we will be blessed as we do his will. In John 14:15 God says, "If ye love me, keep my commandments." If we really have a love for God we will use our agency to follow him because if we don't have a love for him we are choosing to follow the Devil and going against God and his plan. To emphasize just a little bit more another Book of Mormon scripture explains the blessings we can receive if we use our agency to keep God's commandments. Mosiah 2:22 says, "And behold, all that requires of you is to keep his commandments; and he has promised you that if ye would keep his commandments ye should prosper in the land; and he nevr doth vary from that which he hath said; therefore, if ye do keep his commandments he doth bless you and prosper you." Following God can make us happier people as we strive to do his will which is keeping his commandments if we choose not to do so we have used our agency to follow Satan. We all are lucky to have a God that lets us choose how we want to live our lives and gives good reasons and promises why it is that we should follow him.