Answered by Sayyidi Habib Umar bin Hafiz (may Allah protect him and benefit us by him)
Which comes first: certainty (yaqin) or knowledge of Allah (ma`rifah)?
`Ilm al-yaqin (certainty based upon knowledge) opens the door to ma`rifah. `Ayn al-yaqin (certainty based upon witnessing) is part of ma`rifah.