SB 5.20.33
yat tat karmamayam lingam
brahma-lingam jano ’rcayet
ekantam advayam santam
tasmai bhagavate nama iti
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Lord Brahma is known as karma-maya, the form of ritualistic ceremonies, because by performing ritualistic ceremonies one may attain his position and because the Vedic ritualistic hymns become manifest from him. He is devoted to the Supreme Personality of Godhead without deviation, and therefore in one sense he is not different from the Lord. Nevertheless, he should be worshiped not as the monists worship him, but in duality. One should always remain a servitor of the Supreme Lord, the supreme worshipable Deity. We therefore offer our respectful obeisances unto Lord Brahma, the form of manifest Vedic knowledge.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
In this verse, the word karma-mayam (“obtainable by the Vedic ritualistic system”) is significant. The Vedas say, svadharma-nisthah sata janmabhih puman viriñcatam eti: “One who strictly follows the principles of varnasrama-dharma for at least one hundred births will be rewarded with the post of Lord Brahma.” It is also significant that although Lord Brahma is extremely powerful, he never thinks himself one with the Supreme Personality of Godhead; he always knows that he is an eternal servitor of the Lord. Because the Lord and the servant are identical on the spiritual platform, Brahma is herein addressed as bhagavan. Bhagavan is the Supreme Personality of Godhead, Krsna, but if a devotee serves Him with full faith, the meaning of the Vedic literature is revealed to him. Therefore Brahma is called brahma-linga, which indicates that his entire form consists of Vedic knowledge.