“Once, long ago, on the shore of the river Sarasvatī, a discussion arose among a group of sages as to which of the three chief lords — Brahmā, Viṣṇu or Śiva — is the greatest. They deputed Bhṛgu Muni to investigate the matter.
Bhṛgu decided to test the lords’ tolerance, for that quality is a sure sign of greatness. First he entered the court of Lord Brahmā, his father, without offering him any respect. This enraged Brahmā, who suppressed his anger because Bhṛgu was his son. Next Bhṛgu went to Lord Śiva, his older brother, who rose from his seat to embrace him. But Bhṛgu rejected the embrace, calling Śiva a deviant heretic. Just as Śiva was about to kill Bhṛgu with his trident, Goddess Pārvatī interceded and pacified her husband. Next Bhṛgu went to Vaikuṇṭha to test Lord Nārāyaṇa. Going up to the Lord, who was lying with His head on the lap of the goddess of fortune, Bhṛgu kicked His chest. But instead of becoming angry, both the Lord and His consort stood up and offered Bhṛgu respects. “Welcome,” said the Lord. “Please sit down and rest awhile. Kindly forgive us, dear master, for not noticing your arrival.” When Bhṛgu went back to the assembly of sages and told them all that had happened, they concluded that Lord Viṣṇu is certainly supreme.”
Source:A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Tenth Canto, Chapter 89 – Introduction