三生有幸 (sānshēngyǒuxìng): the blessing of three lifetimes

From the Yuan-dynasty zaju play 《东坡梦》 (Dōngpō Mèng) by 吴昌龄: '久闻老师父大名，今日得睹尊颜，三生有幸' — 'Long have I heard the master's name; to behold him today is the fortune of three lifetimes.' 三生 'three lives' draws on the Buddhist 前生今生来生 (past/present/future life) framework: being lucky across all three is the highest honor imaginable.

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Formal and slightly old-fashioned — perfect for a written speech, a wedding toast, or meeting someone you genuinely admire. Saying it about a coffee meeting with a coworker would sound comically over-the-top.