Response:

The tripitakas have never stated that monastics cannot have a lay person as their spiritual teacher. In the different Buddhist schools, many great monastic Buddhist masters have had lay people as their spiritual teachers. Therefore, there is no fault in monastics having a lay person as their spiritual teacher.  

Sutra, Vinaya, Abhidharma

Within Buddhist sutras, there are several accounts of bodhisattvas who are laity that give teachings to monastics and laity at Buddhist ceremonies. For instance, Avalokiteshvara Bodhisattva gives the Prajnaparamita Sutra teachings. The Aspiration of Bodhisattva Samantabhadra is taught by Samantabhadra Bodhisattva. The Demonstration of the Inconceivable State of Buddhahood Sutra is explained by Bodhisattva Manjushri. Sutra of Akashagarbha Bodhisattva is taught by Bodhisattva Akashagarbha. All these bodhisattvas were lay people who gave teachings to both monastics and laity; their teachings have become instructions that all Buddhists abide by.

The vinaya scriptures further state that monastics can receive precepts from lay people. Sarvastivadavinayavibhasha states: "Should there be monks who do not have the required setting and people to receive the precepts from, they may even receive the precepts from a novice nun. The ordination should still be completed in the presence of a strict upholder of ethical discipline. Monks may also receive precepts from lay practitioners."

The Great Treatise on the Stages of the Path to Enlightenment cites Ornament for the Mahayana Sutras when explaining the full qualifications of the spiritual teacher. These requirements include being qualified in the three trainings, having thorough knowledge of reality (skilled in wisdom), and possessing loving concern (compassion); however, the scriptures do not state that a qualified teacher must be a monastic. Therefore, if students are deciding whether they should receive guidance from this spiritual teacher, it is not important whether this teacher is a monastic or not. Rather, it is important to observe whether or not the teacher is qualified as written in the scriptures.

Conducts of past Buddhist masters

The records of past Buddhist masters have also stated that lay practitioners qualify as teachers of monastic students. As recorded in The Blue Compendium, Honourable Je Atisha has said that within Hinayana Buddhism or the sravaka vehicle, monastics can learn from lay practitioners, as long as this lay practitioner possesses a thorough understanding of the tripitakas of Hinayana Buddhism. As for Mahayana Buddhism, if this lay Buddhist teacher has bodhicitta—the spirit of enlightenment—practitioners can follow this lay person as their teacher and will receive blessings. 

Looking at the Buddhist masters, such as Great Master Naropa, who was the former Guardian of the Western Gate at Nalanda Monastery. His primary teacher was in fact a lay practitioner—Master Tilopa. Honourable Je Atisha was viewed as the universal leading master of 18 vinaya schools in India. He resolved any questions and stated what was allowed and prohibited within the vinaya. This great Buddhist master also had abided by the instructions of laity in learning Buddhism [1].

Moreover, Master Gampopa viewed Milarepa as his fundamental teacher. In addition, Sakya Pandita's fundamental teacher was his uncle, the third of the Five Sakya Patriarchs, who was also a lay person. When Great Master Xuan-Zang was studying in India, he learned from the renowned Shilabhadra. However, the teacher whom he learned from and followed for the longest period of time was a lay person named Jayasena. Master Jayasena taught him logic and scriptures related to yoga [2].

The aforementioned Buddhist masters had both theoretical and practical knowledge. From their conduct, one cannot state that monastics cannot have laity as their Buddhist teachers. 

[1]The Biography of Je Atisha as translated by Venerable Master Fa-Zun states: "In addition, when Honourable Je Atisha circumambulated the Defeating Mara Stupa, he received teachings on bodhichitta from two female laity (who were dharkinis). Later, in front of the prayer hall of Tara, he also saw an old and young female laity talking to each other regarding the previously mentioned content."

[2]Tang Dynasty

The Biography of Great Master Xuan-Zang written by Venerable Master Hui-Li details the following:

From here, Great Master Xuan-Zang returned to Zhang-Lin Mountain, where lived his teacher, the lay Buddhist master Jayasena.

Master Jayasena was born in Surastra, within the Kshatriya caste of ruling and military elite. As a child, he loved learning. He first learned Hetuvidya Sastra (logic abhidharma) from the scholar Bhadraruchi, and then learned Shabdavidya Sastra (grammar abhidharma) and Mahayana and Hinayana Buddhist scriptures from Sthiramati Bodhisattva. He studied Yogachara under Venerable Master Shilabhadra. He also widely studied non-Buddhist philosophies, thereby developing a thorough and detailed understanding of the four Veda texts, and other subjects such as astronomy, geography, medicine, astrology. He explored these topics thoroughly, leaving out no detail.

Master Jayasena was well-versed in scriptural knowledge of both Buddhist and non-Buddhist philosophies. As such, his merits and virtues were the most respected by everyone at that time.

At the time, King Manzhou of Magadha was highly admired. He greatly valued people with high moral ethics. Upon hearing of Master Jayasena's distinguishing character, the king became exceptionally delighted. He then sent a messenger to invite Master Jayasena to become the kingdom's advisor. Along with this invitation was a gift of 20 large cities, but Master Jayasena did not accept.

After the passing of King Manzhou, King Shiladitya succeeded the throne. King Shiladitya again invited Master Jayasena to become the kingdom's advisor, this time offering him Kingdom of Udra, which was the size of 80 cities. Once again, Master Jayasena politely declined. King Shiladitya persisted in inviting Master Jayasena to the kingdom, but Master Jayasena resolutely declined each time.

Master Jayasena told King Shiladitya, "I've heard that if one accepts another's compensation, one has to do what that person wants. Currently, the most pressing issue for me is to seek liberation from being bound by the chains of life and death. How would I have time to be involved in the king's affairs?" After saying these words, he bowed to King Shiladitya and left. The king was unable to make him stay.

Thereafter, Master Jayasena resided in the mountain and woods. He accepted and guided students in the study of Buddhism, often giving teachings on sutras. His monastic and lay students, often numbering over hundreds, all abided by his instructions and took refuge in him.

Great Master Xuan-Zang followed and learned from Master Jayasena for two years. He learned many Buddhist texts, including The Commentary on Discerning Vijnanamatra, The Commentary on Meaning of Theory, The Commentary on Becoming Fearless, Non-Abiding Nirvana, Commentary on The 12 Dependent Arisings, Ornament for the Mahayana Sutras. He also received answers to his questions regarding Yogachara, Buddhist Reasoning, and more.

One night, he had a dream. In this dream, Nalanda Monastery had become desolate and dirty. There were no monastics, only buffaloes being raised. Master Xuan-Zang entered the monastery from the west gate of King Youri Court. He saw a golden figure on the fourth floor who looked very dignified; and the interior of the entire building was bathed in light. Master Xuan-Zang's heart was filled with great joy. He wanted to ascend but was unable to. So he asked the golden figure for help.

The golden figure said: "I am Manjushri Bodhisattva. Because you are currently not ready, you are unable to ascend."

He then pointed outside the monastery and said, "Look!" Great Master Xuan-Zang looked at the direction in which the golden figure was pointing and saw that a great fire had burned the village into ashes.

The golden figure said, "You should return home soon. In ten years, King Shiladitya will pass away. India will then be in decline and turmoil. Malevolent individuals will bring harm to all. Remember this." With that, he disappeared.

After Great Master Xuan-Zang woke up, he felt that the dream was strange and was very worried. He went to ask Master Jayasena about the dream. Master Jayasena said, "Nothing is permanent in this world. There is no true safe haven. What you saw in your dream will come true. Since you were informed, you should decide on what to do yourself."

As such, it can be seen that everything Master Xuan-Zang does receives protection and guidance from the bodhisattvas.

Great Master Xuan-Zang then went to India to pay his respects to Master Shilabhadra. Afterwards, he stayed to study Buddhism from Master Shilabhadra. He remained in India for a long period of time and did not return to China. Master Shilabhadra's passing prompted Great Master Xuan-Zang to return home to China and propagate the Buddhist teachings.

If one does not carry a pure aspiration that reflects the intentions of the buddhas and bodhisattvas, how can one receive such blessings?