SB 2.7.41
nantam vidamy aham ami munayo ’gra-jas te
maya-balasya purusasya kuto ’vara ye
gayan gunan dasa-satanana adi-devah
seso ’dhunapi samavasyati nasya param
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Neither I nor all the sages born before you know fully the omnipotent Personality of Godhead. So what can others, who are born after us, know about Him? Even the first incarnation of the Lord, namely Sesa, has not been able to reach the limit of such knowledge, although He is describing the qualities of the Lord with ten hundred faces.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The omnipotent Personality of Godhead has three primary potencies, namely the internal, external and marginal potencies, with unlimited expansions of these three energies. As such, the expansions of His potentcies can never be calculated by anyone because even the Personality of God Himself, as the incarnation of Sesa, cannot estimate the potencies, although He has been describing them continuously with His one thousand faces.