Man’s free agency was activated by the conflicting commandments to not partake of the fruit of the tree of knowledge of good and evil, and to multiply and replenish the earth.
God is in control of his creations. The earth belongs to him. Those who preside over the Mormon Church receive instruction from God with respect to family size and all other religious and moral matters.
If someone does not believe we can become like God, no amount of scriptural evidence will convince him.