This scripture said God "has" given us "everything" we need. Thus, we already have it. The word "everything" means that it has NO boundaries or limitations. There is something, however, that may appear to have boundaries - the actual reality of this fact. However, these limitations or boundaries are illusory and are already dissapearing like the passing night when dawn has arrived, as we are growing in the knowledge of this truth. Who makes us grow? The Holy Spirit. We are in Him and He is in us just as Jesus prayed for in John 17. Thus, we have intimacy (knowledge) with Him. Thus, we know Him. Our knowledge of him, however, grows. Because it grows, we have eternal (never-ending) life, which is why all who are in the kingdom of God are "spitually poor" like Jesus said in the 1st Beattitude. No matter how long we have been "in Christ" and no matter how much we have grown in our knowledge of Him, we will never be as spiritually poor as we are today. The important thing is that we have at least some knowledge of Him, because such knowledge comes from the Deposit which absolutely guarantees our inheritance until Christ returns and claims what are His possessions.
Knowledge of the truth is gradually imparted from His Spirit to our spirit and from our spirit to our minds. At this point our minds perceive the actual true realities Christ spoke into existence. Finally, our bodies are forced to comply with the demands of the mind as the mind conforms to the demands of the Spirit. It is as what was foretold in Genesis 9: Ham (physical body) will be the lowest slave to Japheth (mind) and Shem (spirit), and Japheth's territory will expand as he is renewed in the tents of Shem.
I see something else from this scripture in 2Pet 1:3. Jesus does not need our permission or agreement to create and He creates everytime he opens His mouth and speaks; put another way, Jesus' words are actually accomplished deeds, whether or not we are aware of them or agree with them. For instance, when He created light, He merely said "let there be light" and there was light - whether anyone believed it or not! Also, when Jesus told Philip, "from now on, you do know the Father" - from that point on Philip did know the Father - whether He believed it or not. In the same way, when Jesus tells us that we are happy when we are poor, meek, merciful, hungry, pure in heart, and etc - then we are - whether we believe it or not. Thus, for those who actually believe that God's words are true and authoritative and have thus received the Spirit, they need only to increase in knowledge of His word, by hearing it. As they do this, they will become aware of the true reality of the qualities within and around them. There is one more thing they must do - remember! Just as God at some point in our own lives said to us, "from now on, you do know the Father," if we forget what we heard, we will be like a man who looks at himself in the mirror and later forgets what he looks like. When this happens, the old realities become more real to us than the true realties and we, like Peter, begin to sink deep in sin.
If anyone should panic by realizing the logical truth of this text, they should pray to Jesus, "Lord, I do believe, please help my unbelief" - and the Lord Jesus who cannot lie and has the power to do what He promises, will certainly help his unbelief.