The song 'I Do' by Paul McCartney is a heartfelt love ballad that delves into themes of commitment, devotion, and genuine affection. McCartney expresses his deep love for his partner, emphasizing his willingness to be there for them through all stages of life. Among the key themes are unconditional love, loyalty, and companionship. Particularly poignant moments in the song include the repeated affirmations of 'I do,' signifying a pledge or vow of eternal love, evoking the solemness and beauty of wedding vows.