The Importance of Attending Mangal Arotik (Morning Program at 4:15 am)
In the Sri Gurvastakam by Srila Visvanatha Cakravarti Thakura there is a 9th verse:
srimad guror-astakam etad uccair
brahme muhurte pathati prayatnat
yastena vrndavana-natha saksat
sevaiva labhya janusoÃ‚â€™nta eva
That person who very attentively recites this astakam to Sri Gurudeva during brahma muhurta is sure to achieve direct service to the lotus feet of Sri Krsna, the very life and soul of Vrndavana [vrndavana-natha], upon attaining his vastu-siddhi or pure spiritual form.
Note: The inclusion of this ninth verse at this point in the puja does not necessarily imply that it should be used at other times when the chanting of the Gurvasataka is recited. [from the editors of Arcana-Paddhati].
From this translation we can see the immense benefit of attending the mangal aratik.
In the purport to SB 3.20.46, Srila Prabhupada also says: "The time early in the morning, one and a half hours before sunrise, is called brahma-muhurta. During this brahma-muhurta, spiritual activities are recommended. Spiritual activities performed early in the morning have a greater effect than in any other part of the day."
In Krsna book Srila Prabhupada writes: "Lord Krsna used to lie down with His sixteen thousand wives, but He would also rise from bed very early in the morning, three hours before sunriseâ€¦... After rising from bed, Lord Krsna would wash His mouth, hands and feet and would immediately sit down and meditate on Himself. This does not mean, however, that we should also sit down and meditate on ourselves. We have to meditate upon Krsna, Radha-Krsna. That is real meditation. Krsna is Krsna Himself; therefore He was teaching us that brahma-muhurta should be utilized for meditation on Radha-Krsna. By such meditation Krsna would feel very much satisfied, and similarly we will also feel transcendentally pleased and satisfied if we utilize the brahma-muhurta period to meditate on Radha and Krsna and if we think of how Sri Rukminidevi and Krsna acted as ideal householders to teach the whole human society to rise early in the morning and immediately engage in Krsna consciousness. There is no difference between meditating on the eternal forms of Radha Krsna and chanting the maha-mantra, Hare Krsna."