Catechism of the Catholic Church
270 God is the Father Almighty, whose fatherhood and power shed light on one another: God reveals his fatherly omnipotence by the way he takes care of our needs; by the filial adoption that he gives us ("I will be a father to you, and you shall be my sons and daughters, says the Lord Almighty"): 109 finally by his infinite mercy, for he displays his power at its height by freely forgiving sins.
271 God's almighty power is in no way arbitrary: "In God, power, essence, will, intellect, wisdom, and justice are all identical. Nothing therefore can be in God's power which could not be in his just will or his wise intellect." 110
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English Translation of the Cathechism of the Catholic Church for the United States of America © 1997, United States Catholic Conference, Inc.