A clue can be seen in the passage 1 Corinthians 10:1-4,where it says that the Israelites drank from the Rock and the Rock was Christ. What they experienced was teaching about the Lamb. God created dangerous situations like water and food shortages, and then rescued. This was to teach Israel that not caring about self, not to feed and protect ourselves in order to survive, which is counter intuitive and not what the world follows, would result in God feeding and protecting, and motivate others to abandon the selfish living that scrabbling for worldly resources creates, since they would see that being loving and unselfish would not lead to disaster to their own wellbeing. This power is not focused on sacrifice, but on love.
John 15:13"Greater love has no one than this, that one lay down his life for his friends.
If we offer our bodies to be burned and do not have love, we are empty gongs. That means that the show of power is not gratuitous, like Israel going out to fight the Amalekites because the Spirit had hovered above them, but to be like Jesus, who refused to show off His power that He knew had come upon Him, when asked to jump off the roof of the Temple. The Resurrection, the rescue, after picking up the cross, needed to be done to motivate others to in turn serve God by following in the same gathering of His sheep through picking up a cross.
Paul wanted to be abiding in Christ, by removing all sin from his life, because only the pure can see God. He had been mostly successful, but to prevent him from becoming proud, God allowed a weakness to remain. God also took the opportunity to teach Paul that his performance in sanctification was not the factor in abiding well in Christ, being powerful in gathering, but his faith, loyalty, for which grace was the payback. Because when God did great works in saving, when Paul picked up a cross, the fact that Paul was revealed to be weak only helped to turn the focus on God even more. This is why Moses was rebuked for directing the focus on himself. People are saved not by following Moses or Paul, but by following God.
Numbers 20:12But the LORD said to Moses and Aaron, "Because you have not believed Me, to treat Me as holy in the sight of the sons of Israel, therefore you shall not bring this assembly into the land which I have given them."
God the Son, the Lamb, has always been involved in self sacrifice from the foundation of the world, and manifested this self sacrifice in human form in Christ.
Hebrews 10:5Therefore, when He comes into the world, He says, "SACRIFICE AND OFFERING YOU HAVE NOT DESIRED, BUT A BODY YOU HAVE PREPARED FOR ME;
In summary, the power of Christ is the involvement of God, the finger of God, in situations where the believer intentionally puts himself in danger, picks up a cross everyday, like Jesus did, in confronting the authorities, to serve others by motivating them to imitate their action, because God rescued.
Luke 11:20But if I cast out demons by the finger of God, then the kingdom of God has come upon you.
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Exodus 8:19Then the magicians said to Pharaoh, "This is the finger of God." But Pharaoh's heart was hardened, and he did not listen to them, as the LORD had said.
It is initiated when the believer himself stops working to protect and feed themselves, comes out of Egypt, manifested in the Holy Spirit settling down on them when they rise from the waters of baptism, like it did on Israel and Christ. In other words, demonstrations of the power of Christ is operationalised through the giving of the Holy Spirit, upon baptism, to build up faith. It is given when the believer expresses faith, perfects it with action, which Christ did, but Israel did not:
Hebrews 5:8Although He was a Son, He learned obedience from the things which He suffered.