A.W. Tozer addresses the detrimental effects of complaining on the soul and the Christian testimony, emphasizing that this sin is often overlooked despite its prevalence. He argues that a complaining heart can always find reasons to be unhappy, whether it be about circumstances, the church, or even God. Tozer points out the illogical nature of a Christian's complaints, as they have chosen to follow Christ freely and can leave at any time, yet they persist in grumbling. This contradiction places them in a morally untenable position, undermining their faith and witness. Ultimately, Tozer calls for self-examination and a shift away from a complaining attitude to one of gratitude and faith.

Among those sins most exquisitely fitted to injure the soul and destroy the testimony, few can equal the sin of complaining. Yet the habit is so widespread that we hardly notice it among us. The complaining heart never lacks for occasion. It can always find reason enough to be unhappy. The object of its censure may be almost anything: the weather, the church, the difficulties of the way, other Christians or even God Himself. A complaining Christian puts himself in a position morally untenable. The simple logic of his professed discipleship is against him with an unanswerable argument. Its reasoning runs like this: First, he is a Christian because he chose to be. There are no conscripts in the army of God. He is, therefore, in the awkward position of complaining against the very conditions he brought himself into by his own free choice. Secondly, he can quit any time he desires. No Christian wears a chain on his leg. Yet he still continues on, grumbling as he goes, and for such conduct he has no defense.