Mercury rules over trade, business, law, and communication. For instance, Mercury in Gemini often signifies a career in trading or law, while its interaction with Saturn indicates a business-oriented profession.
Planets in the same "direction" (1st, 5th, and 9th signs from each other) are considered conjunct. If Mercury is in a trine with benefic planets, the native will enjoy smooth educational progress. Budha Nadi Pdf
Mercury is the "destiny maker" for intellectual pursuits. Its position relative to Jupiter (the life force) determines a person's learning capacity and academic milestones. Mercury rules over trade, business, law, and communication