How did Jesus activate his powers?

[Sacred Fool]

Still I don't understand how Jesus who was at the edge of 4th/5th density could remember so much and activate his powers and thereby affect every single human being on this planet after his death. Yet there are 6th density wanderers here walking around like normal people who don't even know it. How is this possible? They are literally billions of years more spiritually advanced. Shouldn't they at least remember a bit more?

I find your question amusing.

I would point out that Jesus' profound effect upon world culture occurred centuries after his departure from the warm and fuzzy confines of our 3d Earth plane illusion.  The reasons for the reception of Paul's concept of debt and repayment (Adam sinned and Jesus paid the price for all of us) had a lot to do with the cultural politics and decline of other religions at the end of the Roman Empire.  Jesus wasn't there then selling his "gospel."  His narrative-cum-teachings became a useful focus for the religious currents of that age, and of succeeding ages.

That said, your question stands: Why was Jesus able to open his personal awareness so deeply that he could align his will with that of Divinity? 

I might suggest that the true answer to your question cannot be contained by words.  The answer you seek is of Spirit, not of thought.  Ergo, seek not with your mind, but with your very spirit.