(Spiritual Communion is an ardent desire to receive Jesus Christ in the Most Holy Sacrifice, and a heartfelt welcome as if we had actually received Him.  A fervent Spiritual Communion sometimes produces results similar to those of actual Communion.... We may make a Spiritual Communion frequently during the day.  This pious practice tends to increase our devotion to Jesus in the Sacrament of His Love, and our fervor in the reception of Holy Communion.)

My Jesus, I believe that You are present in the Most Holy Sacrament. I love You above all things and I desire to possess You within my soul. Since I cannot now receive You sacramentally, come at least spiritually into my heart. I embrace You as being already there and unite myself wholly to You; never permit me to be separated from You.

(1943 Manual of Prayers for Those Serving Our Country)