Duties of the citizen
Section 24 · 1999 Constitution (2004 edition)
What Constitution says
It shall be the duty of every citizen to - (a) abide by this Constitution, respect its ideals and its institutions, the National Flag, the National Anthem, the National Pledge, and legitimate authorities; (b) help to enhance the power, prestige and good name of Nigeria, defend Nigeria and render such national service as may be required; (c) respect the dignity of other citizens and the rights and legitimate interests of others and live in unity and harmony and in the spirit of common brotherhood; (d) make positive and useful contribution to the advancement, progress and well-being of the community where he resides; (e) render assistance to appropriate and lawful agencies in the maintenance of law and order; and (f) declare his income honestly to appropriate and lawful agencies and pay his tax promptly.
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 30. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections