He cupped his fist in salute to pay his respects to his master.
Tips
culture
Right fist (representing 武 'martial' force) wrapped by an open left palm (representing 文 'civility / restraint') — symbolises that the warrior's strength is contained by virtue. Standard greeting in 武术 (wǔshù) schools and at lion-dance and Spring Festival kung-fu performances.
usage
Distinct from 作揖 (zuòyī, generic clasped-hands bow) — 抱拳礼 is specifically the kung-fu world's salute. You'll see it before sparring matches, in period dramas, and when 江湖 characters greet one another.