The Seven Sorrows of Our Lady

The Seven Dolors or Sorrows of Mary:

1. The prophecy of Simeon (Luke 2:25-35)
2. The flight into Egypt (Matthew 2:13-15)
3. Loss of the Child Jesus for three days (Luke 2:41-50) 
4. Mary meets Jesus on his way to Calvary (Luke 23:27-31; John 19:17)
5. Crucifixion and Death of Jesus (John 19:25-30)
6. The body of Jesus being taken from the Cross (Psalm 130; Luke 23:50-54; John 19:31-37)
7. The burial of Jesus (Isaiah 53:8; Luke 23:50-56; John 19:38-42; Mark 15:40-47)

From the Holy Gospel according to John
John 19:25-27
At that time: There stood by the Cross of Jesus His Mother, and His Mother's sister, Mary (the wife) of Cleophas, and Mary Magdalene. And so on.

Homily by St. Ambrose, Bishop of Milan.
On Virgins, 7.
There stood by the Cross His Mother. Men had forsaken Him, but she stood there fearless. Behold how the Mother of Jesus could break through her shrinking modesty, but could not belie her heart. With the eyes of a mother's love she gazed upon the Wounds of her Son, those Wounds through Which she knew that redemption for all mankind was flowing. The Mother, who feared not the executioners, was able to endure the sight of their work. Her Son was hanging upon the Cross, and she braved His tormentors.

From the same 25th Epistle to the Church of Vercelli.
Mary, the Mother of the Lord, stood by the Cross of her Son. My only informant of this fact is the holy Evangelist John. Others have written that when the Lord suffered, the earth quaked, the heavens were veiled in darkness, the sun was hidden, and the thief received, after a good confession, the promise of Paradise. John hath taught us what the others have not taught us. Upon the Cross He called her Mother. It is reckoned (by John) a greater thing that in the moment of triumph over agony, He should have discharged the watchful duty of a Son to His Mother, than that He should have made gift of the kingdom of heaven. For if it be a sacred thing to have forgiven the thief, this so great kindness of the Son to the Mother is to be worshipped as the outcome of a tenderer and more touching love.

Behold, saith the Lord, thy son: Behold thy Mother! Christ bore witness from the Cross, and divided the offices of his tender love between his Mother and his disciple. Thus doth the Lord give us a testament, not only of his love for souls, but also of his natural affection. Moreover, the testimony which John doth give us concerning this same testament, is a worthy testimony to the original Testator himself. It is a good testament, not of earthly riches, but of eternal life, written not in ink, but in the Spirit of the living God, who speaketh of such testimony in the Psalms, saying: My tongue is the pen of a ready writer.