The first characteristic listed as a requirement for deacons is "seriousness." This characteristic is also the first requirement listed for their wives (1 Tm 3:11). This same trait is expected of bishops, that is, overseers of communities. The word is here translated "dignity" and applied to the overseers' parenting (1 Tm 3:4; see also 1 Tm 2:2, NAB).
Seriousness or dignity is expected of the older men in the Christian community (Ti 2:2). It is also a characteristic of good teaching (Ti 2:8). In the King James translation, the word for "seriousness" and "dignity" is translated "gravity." This could indicate that, just as gravity is an unstoppable force, seriousness in living the Christian life produces solid, lasting fruit which cannot be overcome. In summary, seriousness is necessary for deacons, their wives, leaders of Christian community, elderly Christian men, and good teaching. Therefore, seriousness is obviously very important in the Christian life.
However, this doesn't mean that Christians should take themselves too seriously. Rather, we should take God very seriously. The fear of the Lord is the beginning of wisdom (Ps 111:10) and of holy seriousness. Christianity is not just a matter of life or death but of everlasting salvation or damnation. Because Christianity is serious, it is wonderful and joyful. Christianity is serious love. Jesus is serious enough about loving us so as to die on the cross. He was "dead serious." He is "live serious." Are you?