By nature some persons fret easily. They have difficulty separating their personal antipathies from the burden of the Spirit. When they are grieved they can hardly say whether it is a pure and charitable thing or merely irritation set up by other Christians having opinions different from their own.
Of one thing we may be sure, we can never escape the external stimuli that cause vexation. The world is full of them and though we were to retreat to a cave and live the remainder of our days alone we still could not lose them. The rough floor of our cave would chafe us, the weather would irritate us and the very silence would cause us to fret.
Deliverance from a fretting spirit may be by blood and fire, by humility, self-abnegation and a patient carrying of the cross. There will always be "evildoers" and "workers of iniquity," and for the most part they will appear to succeed while the forces of righteousness will seem to fail. The wicked will always have the money and the talent and the publicity and the numbers, while the righteous will be few and poor and unknown. The prayerless Christian will surely misread the signs and fret against the circumstances. That is what the Spirit warns us against.
Let us look out calmly upon the world; or better yet, let us look down upon it from above where Christ is seated and we are seated in Him. Though the wicked spread himself like "a green bay tree" it is only for a moment. Soon he passes away and is not. "But the salvation of the righteous is of the Lord: he is their strength in the time of trouble." This knowledge should cure the fretting spirit.