SB 3.9.18

yasmād bibhemy aham api dviparārdha-dhiṣṇyam
 adhyāsitaḥ sakala-loka-namaskṛtaṁ yat
tepe tapo bahu-savo ’varurutsamānas
 tasmai namo bhagavate ’dhimakhāya tubhyam
Synonyms: 
yasmāt — from whom; bibhemi — fear; aham — I; api — also; dvi-para-ardha — up to the limit of 4,300,000,000 × 2 × 30 × 12 × 100 solar years; dhiṣṇyam — place; adhyāsitaḥ — situated in; sakala-loka — all other planets; namaskṛtam — honored by; yat — that; tepe — underwent; tapaḥ — penances; bahu-savaḥ — many, many years; avarurutsamānaḥ — desiring to obtain You; tasmai — unto Him; namaḥ — I do offer my obeisances; bhagavate — unto the Supreme Personality of Godhead; adhimakhāya — unto Him who is the enjoyer of all sacrifices; tubhyam — unto Your Lordship.
Translation: 
Your Lordship, I offer my respectful obeisances unto You who are indefatigable time and the enjoyer of all sacrifices. Although I am situated in an abode which will continue to exist for a time duration of two parārdhas, although I am the leader of all other planets in the universe, and although I have undergone many, many years of penance for self-realization, still I offer my respects unto You.
Purport: 

Brahmā is the greatest personality in the universe because he has the longest duration of life. He is the most respectable personality because of his penance, influence, prestige, etc., and still he has to offer his respectful obeisances unto the Lord. Therefore, it is incumbent upon all others, who are far, far below the standard of Brahmā, to do as he did and offer respects as a matter of duty.