From Rabbi Avraham ben HaRambam (Maimonides), Sefer HaMaspik (“The Guide to Serving God”), translated by Rabbi Yaakov Wincelberg (Feldheim Books), pp. 529-531. Although footnotes have been omitted, we have added explanatory information in parentheses.
The most desirable form of retreat is to stand in prayer at the end of the night, having risen at midnight, as it says, “Rise and cry out at night, at the beginning of the watches; [let your heart flow like water, in the presence of God]” (Eichah 2:19). And David said, “My eyes have preceded the watches, to speak of Your word" (Tehillim 119:148). He also said, “At midnight, I arise to thank You for Your just judgments” (v. 62). One following this path might not sleep at all for some of the nights of his retreat, in accordance with the verse, “I will not give sleep to my eyes, slumber to my eyelids...” (ibid. 13 2:4). And Assaf said, “You hold open my eyelids; I am dumbstruck” (ibid. 77:5).
The Sufis practice retreat in dark places, remaining there until the sensitive part of the soul becomes atrophied and cannot even perceive light. This requires a strong inner light to engage the soul, so that it will not be disturbed by the outer darkness. Rabbi Avraham HaChasid understands that this behavior, seclusion in the dark, is mentioned in the verse, “Who among you fears God, listening to the voice of His servant, walking in darkness with no light? He should trust in the Name of the Almighty and rely on his God” (Yeshayahu 50:10). But we have drawn from that verse the concept we explained in the first preface to this work.
The great sages would bless one another, saying, "May God enable you to feel companionship in solitude and loneliness in a crowd” (cf. Chovos HaLevavos, Sha’ar HaBitachon, ch. 7 and Sha’ar Ahavas Hashem, ch. 3). David described his intimacy with God when retreating in the dark of night and in deserts and wastelands – “Even when I walk in the valley of the shadow of death, I fear no evil, for You are with me. Your guidance and Your support comfort me” (Tehillim 23:4). This way is the last of the higher stages, and brings to Encounter. Outward retreat is part of the journey, while inward retreat begins as a journey, but ends as the destination. And “the last one is equal to all the rest.”