You can be a happy family if you will do what God has given you to do and has enjoined upon you as a duty. But the Lord will not do for you that which He has left for you to do. Brother C deserves pity. He has so long felt unhappy that life has become a burden to him. It need not be thus. His imagination is diseased, and he has so long kept his eyes on the dark picture that if he meets with adversity or disappointment, he imagines that everything is going to ruin, that he will come to want, that everything is against him, that he has the hardest time of anyone; and thus his life is made wretched. The more he thinks thus, the more miserable he makes his life and the lives of all around him. He has no reason to feel as he does; it is all the work of Satan. He must not suffer the enemy thus to control his mind. He should turn away from the dark and gloomy picture to that of the loving Saviour, the glory of heaven, and the rich inheritance prepared for all who are humble and obedient, and …
"Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things."
Philippians 4:8 encourages focusing on positive and virtuous thoughts. EGW similarly advises turning away from dark and gloomy pictures and focusing on the loving Savior and heavenly inheritance. The principle of focusing on positive and uplifting thoughts is directly present in both passages.
"Take therefore no thought for the morrow: for the morrow shall take thought for the things of itself. Sufficient unto the day is the evil thereof."
Both passages address the issue of worry and anxiety. EGW speaks of Brother C's tendency to dwell on negative thoughts about the future, while Matthew 6:34 advises against worrying about tomorrow. The connection is thematic, focusing on the importance of not being consumed by anxieties about the future.