Another characteristic of God generally agreed among Christians is that He is omnipotent, meaning to be almighty or infinite in power.  There are many references in Scripture that speak to this:

Job 42:2 I know that thou canst do all things, and that no purpose of thine can be thwarted.

Matthew 19:26 But Jesus looked at them and said to them, “With men this is impossible, but with God all things are possible.”  (Mark 10:27)

Mark 14:36 And he said, “Abba, Father, all things are possible to thee; remove this cup from me; yet not what I will, but what thou wilt.”

Luke 1:34,37 And Mary said to the angel, “How can this be, since I have no husband?”….  For with God nothing will be impossible.

Romans 1:20 Ever since the creation of the world his invisible nature, namely, his eternal power and deity, has been clearly perceived in the things that have been made.

Other verses to consider: Jeremiah 10:12, Isaiah 40:12, Daniel 2:20-22,Job 37:23, Amos 4:13, Romans 4:17, John 1:3-5, Colossians 1:17, Hebrews 1:3, Revelation 1:8, Revelation 19:6.

But what does the understanding of God’s omnipotence mean, exactly?

I will often ask the question in class if God can do anything, and usually I receive a chorus of “yeses” in return.  I then ask the question, “Can God commit an evil act?”  That causes pause.  Of course, we would believe that God would never commit an evil act.  But could He?  Does He simply choose not to do so?

The Catechism of the Catholic Church puts it this way:

CCC271 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.“

God’s power is not “arbitrary” according to the Church, and arbitrary is defined as being “based on or determined by individual preference or convenience rather than by necessity or the intrinsic nature of something.”

We also know that since God does not change (Part 1, Part 2), He doesn’t make “decisions.”  He doesn’t consider two possible actions, and then choose one.  He doesn’t move from a state of “not knowing” what He will do, to “knowing” what He will do.  So the Church would not believe that it is within God’s power to commit an evil act and He chooses not to.  Rather the Church would view that committing an evil act cannot be within God’s power because it could not be “in his just will or his wise intellect.”  It’s simply contrary to His very nature.  So for example, while we would agree with this Evangelical view that God is omnipotent, we would disagree with the view expressed that God does not lack the power to lie but He chooses not to.  

The word omnipotent comes from omni- meaning “all” and potent meaning “power.”  As with the attributes of omniscience and omnipresence, it follows that, if God is infinite, and if He is sovereign, which we know He is, then He must also be omnipotent.  He has all power over all things at all times and in all ways…..

Being omnipotent, God can do anything.  However, that doesn’t mean God has lost His omnipotence when the Bible says that He cannot do certain things.  For example, Hebrews 6:18 says that He cannot lie.  That does not mean He lacks the power to lie, but that God chooses not to lie in accord with His own moral perfection.  In the same way, despite His being all-powerful and hating evil, He allows evil to happen, according to His good purpose.  He uses certain evil events to allow His purposes to unfold, such as when the greatest evil of all occurred—the killing of the perfect, holy, innocent Lamb of God for the redemption of mankind.

https://www.gotquestions.org/God-omnipotent.html

Why is this topic that important?  This can often become one of mental “jumping through hoops” with unbelievers.  Questions like, “can God create a rock so big He can’t lift it?” come to mind.  The intent is to create a scenario that shows that there are things God can’t do, so therefore the idea of an omnipotent being is not logical.

CS Lewis addresses this question in his book “The Problem with Pain.”  He writes “His Omnipotence means power to do all that is intrinsically possible, not to do the intrinsically impossible.  You may attribute miracles to him, but not nonsense.  This is no limit to his power….It is no more possible for God than for the weakest of his creatures to carry out both of two mutually exclusive alternatives; not because his power meets an obstacle, but because nonsense remains nonsense even when we talk it about God.”

So, can God do something like make a square triangle?  According to Lewis, no.  That would be carrying out two mutually exclusive alternatives.  After all, God created squares to have four sides and triangles to have three, and this would not be a limitation to His power.  And the thought that God could commit an evil act contradicts His very nature.  As Lewis says, His inability to do these things isn’t because His power has met an obstacle, but because “nonsense remains nonsense even when we talk it about God.”