There are two paths to power, the masculine and the feminine, and the absolute of these two paths are represented by the Magus and the Priestess. The Chariot and Strength represent their respective powers in action.
The power of the Magus lies in altering the rest of the universe to conform to his will. Their is a duality in the Magus’ perspective of the universe since there is him and there is everything else (in this way he differs from the Fool who exists as a singularity; he is everything). The magus decides what he wants, and then he exerts his will to change the universe to change it. He is masculine. He forces his will onto the universe.
His power in action is represented by the chariot, where a figure has bound two animals together in order to carry him. In some instances these animals are the sphinx, which was defeated by Oedipus when he discovered the sphinx’s secret. This implies that the secret to the Magi’s power lies in acquiring secret information. In some instances the Magus is not being carried across land, but rather through the clouds, implying a spiritual rather than physical power. In any case, the important fact about the chariot is that the Magus has used his power to bind these creatures so that his will can be forced into the universe.
The converse of this power is the feminine power represented by the Priestess. The Priestess is entirely receptive. In her absolute state she allows the entirety of the universe to pass through her. She becomes one with the universe and aligns herself with its will.
Her power in action is represented by the strength card. Here we have a woman holding open or shut the jaws of a lion. The card itself corresponds to Leo. The constellation of Leo is in reference to the indestructible lion killed by Hercules, which is the lion represented in the card. And here we a woman who does not appear to be physically strong and yet she is able to hold open the mouth of this super-lion.
The woman can do this because her will is aligned with the lion’s. The lion wishes for her to hold open his mouth, and so she is able to hold open the lion’s mouth, and is aided in opening the lion’s mouth by the lion’s own jaw muscles.
In the same way neither the lion nor the woman need to be bound here. Both have the same wants, and both are working towards the same goals.
In a lot of ways the differences come down to swimming against the current and swimming with it. The Magus makes himself very powerful so that he can exert large amounts of energy to bring about change in the universe. Meanwhile the Priestess moves with the universe, she aligns herself with its will, and she works within the directions that the universe takes her, and consequently she is able to bring about changing by exerting very little power because the universe is doing most, if not all, of the work.