What follows is a selection from St. Alphonsus's list of "considerations" on God's spiritual mercies, and how we can receive them. They are listed below in order, in the saint's own words, but without the extended explanation that he provided for each one.
1. The necessity of obedience to your confessor.
2. When you suffer misfortune of any kind, endeavor to accept whatever comes as coming to you from the hand of God. ... Say simply, the Lord has permitted me to bear these sufferings not because He dislikes me but because He loves me. And shall I not therefore accept them with resignation?
3. The Lord is full of goodness to those who seek Him. No one has ever trusted in the Lord and been rejected.
4. When souls seek to love the Lord, He finds it impossible not to love them in return.
5. Souls who love their crucified Lord in the midst of their own desolation grow closer to Him in their hearts.
6. To advance in the way of holiness it is necessary above all else to concentrate one's efforts on loving God.
7. In your prayers do not neglect to offer yourself to God unreservedly. From your heart say: "My Jesus, I give myself to You without reserve. I wish to be wholly Yours."
8. When you experience great aridity of spirit, be sure then to rejoice unselfishly in the bliss your God enjoys in heaven. This is an anticipation on earth of that perfect act of love of the blessed in heaven, since they do not so much rejoice in their own happiness as in the infinite happiness of God Himself. They love God much more than they love themselves.
9. As regards your prayers and reflections, never neglect to meditate on the Passion of Jesus Christ. There is no other subject more calculated to elicit our love than the thought of the sufferings of Jesus Christ.
10. Place yourself on the Hill of Calvary, where you will find your Lord dying on the Cross, consumed with sufferings. Seeing Him in this terrible condition, is there any way you could refuse to undergo willingly all types of suffering for a God who dies out of love for you?
11. I recommend prayer to you above all else. When you can say nothing else, simply say, "Lord, help me, and help me without delay."
12. When you ask for graces from God, make sure you ask them in the name of Jesus Christ. ... So when you fear that God will send you to hell, think for a moment how could it be possible that one who has said to you that whatever you ask Him [in His name] will be granted, would send you to hell!
13. How is it that you think you are not pleasing to God when you suffer desolation in spirit? Rather than being worried you should feel reassured, since God is dealing with you in the very same way that He treats His most intimate friends.
14. Keep on praying to Him with love and tenderness and have no anxiety that He will abandon you. Say in the words of the apostle ... [nothing can] separate us from the love of God in Christ Jesus our Lord (Rom 8:38-39).
15. When you are oppressed by fears for your salvation or by desolation of spirit, do not neglect to have recourse to Our Lady, who has been given to us by God as the Consolatrix of those who are afflicted.
16. The more trust we have in the Lord the more we receive from Him. He Himself has declared that He rewards those who trust Him.
17. The Lord has declared that His great joy is to be with us: "And I found delight in the sons of men" (Pr 8:31). ... This thought alone should encourage us to pray to God with all confidence.
18. My God, why is it that scrupulous and anxious souls treat You as if You were a tyrant who demands nothing more from Your subjects than fear and trepidation? The result is they think that God gets angry at every thought that passes through their minds and at every word that slips involuntarily from their lips and wishes to cast them into hell.
19. God's infinite majesty certainly deserves all our reverence and submission, but He Himself prefers to receive from souls desirous of loving Him their love and confidence rather than fear and servility.
20. Frequent reception of the sacraments [St. Alphonsus here directly opposes the teachings of the Jansenist heretics, who demanded near perfect contrition for sin before a soul could dare to go to confession and receive Holy Communion].
21. Your love should be centered above all else on the two great mysteries of our Lord's love, the Holy Sacrament of the Altar and the Passion of Jesus Christ. If the love of all human hearts could be concentrated in one heart it would not approach in the slightest degree to the greatness of the love which Jesus Christ has shown us in these two mysteries. And so, in short, concentrate all your efforts for the future on love for God, and confidence in His great mercy.
[Quotations from St. Alphonsus' essay "Motives for Confidence in the Divine Mercy" are taken from Alphonsus Liguori: selected writings, New York: Paulist Press, Classics of Western Spirituality series, 1999