The "soft" and "hard" distinctions were much more fluid than in modern grammar.
A late 14th-century trilingual prayer book (Latin, Polish, and German) designed for Queen Jadwiga. ⚔️ Knights and Hymns: Cultural Milestones Medieval subtitles Polish
If you were to "subtitle" a medieval Pole today, the language would look and sound significantly different: The "soft" and "hard" distinctions were much more
As the Middle Ages progressed, Polish moved from simple marginal notes to full literary compositions. Bogurodzica (Mother of God) Medieval subtitles Polish