Head and heart
Acts 8: 22
“Repent of this wickedness and pray to the Lord. Perhaps he will forgive you for having such a thought in your heart.”
So long as I don’t do the deed then it’s okay to think it. Clearly not!
Simon offered to buy with money the gift of God, it was stupid and impossible. He wasn’t being chastised for the act but the thought. Thoughts do matter. It’s not okay to think certain things.
Repent (change your mind) for you have a thought problem of the heart. Mind and heart.
I would say, desire and motive, turn from them and perhaps God will forgive you. This doesn’t sound certain but only because there is nothing certain as to whether Simon will do what is being suggested to him.
May today your desires be for Him and your motives be for His glory and for others. May you not come into the equation at all.