The Bible verse is Matthew 6:33, But seek ye first His kingdom, and His righteousness; and all these things shall be added unto you. 34 Be not therefore anxious for the morrow:….
John Calvin talks about “restraining excessive anxiety”. Of course, excessive anxiety can arise in many areas of life such as money, time, relationships, work or societal issues.
John Calvin says: But rather seek first the kingdom of God. This is another argument for restraining excessive anxiety about food. It argues a gross and indolent neglect of the soul, and of the heavenly life. Christ reminds us that there is the greatest inconsistency in men, who are born to a better life, being wholly employed about earthly objects. He who assigns the first rank to the kingdom of God, will not carry beyond moderation his anxiety about life. Nothing is better adapted to restrain the wantonness of the flesh from breaking out in the course of the present life, than meditation on the life of the heavens. The word righteousness may be either understood as applying to God, or to the kingdom: for we know that the kingdom of God consists in righteousness, ( Romans 14:17 ,) that is, in the newness of spiritual life. All other things shall be added. This means, that those things which relate to the present life are but favorable appendages, and ought to be reckoned greatly inferior to the kingdom of God. – from the John Calvin Commentary.