Dr. John MacArthur teaches that “no infraction against God’s holiness is a trifling thing, and each person will ultimately give account of such indiscretion” (The MacArthur Bible Commentary, p. 1,146). The Lord hears and remembers every word we speak; therefore, we should not think there is such a thing as a throwaway phrase. How thoughtful are you before you speak, and what do your jokes and whispered comments say about the state of your heart?
For further study:
The Bible in a year: