Spiritual Emotion is a state experienced in the Path of Devotion (Bhaktiyoga).
Devotees of God live in a mood of ecstasy and self-surrender.
Sri Radhika Rani is the greatest devotee of Lord Krishna filled with Spiritual emotion. It is said that Sri Radha is herself the "Devotional energy" of Lord Krishna who is the Lord of the universe
As per as the Bhagavad Gita, devotion is the easiest method to develop "Bhaav" and get close to Krishna. God himself declares about the glory of devotion in Bhagavad Gita:
Bhagavad Gita Chapter 12
TEXT 8
mayy eva mana adhatsva
mayi buddhim nivesaya
nivasisyasi mayy eva
ata urdhvam na samsayah
SYNONYMS
mayi--unto Me; eva--certainly; manah--mind; adhatsva--fix; mayi--upon Me; buddhim--intelligence; nivesaya--apply; nivasisyasi--you live; mayi--unto Me; eva--certainly; atah urdhvam--thereafter; na--never; samsayah--doubt.
TRANSLATION
Just fix your mind upon Me, the Supreme Personality of Godhead, and engage all your intelligence in Me. Thus you will live in Me always, without a doubt.
So let's have devotion towards Krishna. Let's remember Krishna in our daily life so that we can generate "Bhaav" or "Spiritual Emotion" towards him.
