All the prophets observe these two foremost commandments. Loving God with all your heart means to love Him with the love that you feel for the person who is dearest to you – with the love of the mother or father for the child, or the lover for the beloved. Give that kind of unconditional love to God. Loving God with all your soul means you can truly love Him when through deep meditation you know yourself as a soul, a child of God, made in His image. Loving God with all your mind means that when you are praying, your while attention is on Him, not distracted by restless throughts. In meditation, think only of God; don’t let the mind wander to everything else but God. That is why yoga is important; it enables you to concentrate. When by yoga you withdraw the restless life force from the sense nerves and become interiorized in the thought of God, then you are loving Him with all of your strength – the whole of your being is concentrated in Him.
– Sri Sri Paramahansa Yogananda
Journey to Self-Realization
“Probing The Core of Nervousness”, page 96-97