For the king of Celtic soul, emotions always run deep. As a result, Van Morrison’s songs can feel like raging torrents (“Gloria”) or be as sweet and tender as lullabies (“Into the Mystic”). Either way, the richness and intensity of his music are undeniable. And while those qualities can make them daunting challenges for performers hoping to make Morrison’s songs their own, great rewards await those brave enough to sail these stormy waters.