You have a MAJOR MISUNDERSTANDING of both passages of Scripture. Nowhere did Jesus say that Christians are "gods". That is the lie which the Devil put forward at the beginning -- "ye shall be as gods" and the end result was the exact opposite.
The Word of God came to all of Israel, so by your logic, all Israel would have been gods. But that is not the meaning of that phrase at all. Notice to whom God was speaking in this Psalm:
God standeth in the congregation of the mighty; he judgeth among the gods. How long will ye judge unjustly, and accept the persons of the wicked? Selah. Defend the poor and fatherless: do justice to the afflicted and needy. Deliver the poor and needy: rid them out of the hand of the wicked.
So the judges (magistrates) of Israel are called "the mighty" and "the gods", but at the same time they are soundly rebuked for their injustice, their oppression, and their wickedness.
The judges of Israel stood in the place of God to dispense justice. That is why they were called "gods" (the mighty ones) and this is evident in "the congregation of the mighty".