Srimad-Bhagavatam: Canto 7 - Chapter 1 - Verse 23
Sanskrit:
देवगुर्वच्युते भक्तिस्त्रिवर्गपरिपोषणम् ।आस्तिक्यमुद्यमो नित्यं नैपुण्यं वैश्यलक्षणम् ॥ २३ ॥
ITRANS:
deva-gurv-acyute bhaktistri-varga-paripoṣaṇamāstikyam udyamo nityaṁnaipuṇyaṁ vaiśya-lakṣaṇam
Translation:
Being always devoted to the demigods, the spiritual master and the Supreme Lord, Viṣṇu; endeavoring for advancement in religious principles, economic development and sense gratification [dharma, artha and kāma]; believing in the words of the spiritual master and scripture; and always endeavoring with expertise in earning money — these are the symptoms of the vaiśya.