After many years of searching for a solution to my natural tendency of worrying, I finally found it in the well-known verse 2.47 of the Bhagavad-Geeta. I had read this verse many times, but I was restricting myself to the first line and ignoring the second line, assuming that to be unimportant.
Reading the second line of the verse properly, everything becomes clear. The first part of the second line clarifies the position of the second part of the first line. It states: You should not try to speculate about the fruits of action. Lord Krishna knew that the second part of the first line would cause confusion if left unexplained. This is why He clarified what He meant in the second part of the first line.
And the best part is contained in the last part of the second line. After stating that you have a right only in action and then stating quite forcefully in the second part of the first line and clarifying this instruction in the first part of the second line that you have no right to speculate about the fruits, Lord Krishna gives an alternative to such speculation. Once we have done something, it is very natural to speculate about the result or even get attached to some specific result.
How can this natural propensity be curbed? This is what the Lord states in the last part of the second line. He states that your attachment to inaction should not be there, because this is exactly what we do after doing some action. If we are really desirous of some result, should we not continue to strive for it? But we don’t and take the easier option of speculating.
Therefore, let us stop worrying. If we are really concerned, then we should act suitably, and not just keep on worrying.