I have already explained the so called mistakes done by God (people think it in that way) as the lila via Maya.
That Lila of Shiva and Mohini mentioned in multiple Puranas are not to downgrade Mahadeva and there’s nothing controversial in it unless some Anti-Hindu deliberately misuses the story to put false allegations on Sanatan Dharma.
In the story where Shiva gets attracted towards Mohini (the female form or the illusionary form, i.e. Vishnu Maya), the word 'Maya’ is used quite often. So the lila was done to show the power of Maya and not lack of self control of Shiva. Ordinary beings are under the control of Maya but Shiva is not under the control of Maya, he can engage in such lila where he appears or portrays himself to be overpowered by it but in his original state, he is unaffected and absolutely still.
It is very much like a film in which a character does a scene where he acts in the same manner as mentioned in script, in the same way Shiva being the Supreme Consciousness is completely aware of everything but he engages himself in a lila which might not sound very pleasing but it would still had a greater purpose.
There is a very deep meaning in that story. and all the so called controversial acts by God (like these sensual and intimate stories) in Puranas they are nothing but the acts performed by God not out of ordinary lust like human beings and animals but using Kama to generate a new form (either a powerful deity or some element).
So in Puranas, we have two most famous stories of Shiva associated with Kama (lust). First is when he burns Kama with his third eye and Kama actually turns into ashes. This was when Shiva was in deep samadhi and Kama shot his cupid 💘 on Shiva so that he can have a union with Goddess Parvati which would lead to the birth of Kartikeya who will destroy the Asuras including their King Tarakasura who got the boon from Brahma that only the son of Shiva would slay him. Even in that particular event, Bhagwan Shiva did admire Maa Parvati'a beauty in a poetic manner comparing her face with moon and calling her the store house of beauty but the very next moment he opened his third eye and burnt down Kamadeva, proving that he can simultaneously be Maa Parvati’s lover as well as the destroyer of unwanted lust.
Second is this Mohini story where he gets awestuck.. in simple words, he gets attracted towards Goddess Mohini and chases her. Now here the context was different, in the story where he burnt Kama, it was the proof that without his own will, Kama cannot cause any desire in him like it can do with others.
So definitely that act had a divine purpose, it is not to be considered literally as the loss of control but rather a deliberate lila where he emits his semen. Now that seed again is not to be considered as some sticky fluid of a man but the “Tej” of Ishwara because it clearly describes what actually is the result of that act. The entire creation itself is said to be his seed (he is described as Bijavan).
According to Shiva Purana, Shiva emits that seed and it later results in the incarnation of Bajrangabali Hanuman. According to Bhagavat Purana where is described in such way, the drops of his seed forms the gold and silver ores. According to Agni Purana, those drops form Shiva Lingas. And most important story about the union of Shiva and Mohini is mentioned in Brahmanda Purana because the lila was specifically done for that.
As per Brahmanda Purana, Mahishi the sister of Mahishasur had a boon that she can be killed only by the son of Shiva and Vishnu. Now Shiva and Vishnu being the male forms of Ultimate Consciousness, it was important for one of them to become Goddess. Since this “Maya” is the medium, it was Mahamaya (Maheshwari), i.e., Goddess Parvati who gave her own form to God Vishnu who is described meditating on her. Vishnu then turns into Mohini, Shiva gets enchanted (out of his own will) and Aiyyapan is born who then slays Mahishi.
That was the main purpose of the Shiva Mohini Lila.
Now here comes to most important factor that the name “Mohini” is actually mentioned in Lalita Saharasanama (1000 names of Goddess Lalita Tripurasundari, the Ultimate form of Parvati). Mohini as the name of Lalita is at number 562. It means Vishnu assumes the form of Mohini (enchanting feminine) while Lalita/Parvati is Mohini, the enchanting divine feminine.
Further Lalita Tripurasundari is described as Shambhu Mohini which means “the one who enchanted Shambhu i.e. Shiva”. It confirms it further that any form which attracts Shiva is that Shakti only.
So it was Parvati herself who enchanted Shiva through Vishnu as she is the Feminine side of the Ultimate Power. Even Bhagavata Purana describes Goddess Durga as Vishnu’s Maya, so Maya itself is her own aspect and she would enchant everyone. Even Madhu and Kaitabha were deluded by her.
So Mohini definitely is the same Supreme Shakti Lalita Tripurasundari.
If it is Lalita herself who attracts Shiva then why do Bhagavat Purana and Brahmanda Purana etc. describe Parvati getting embarrassed or envious seeing that act?
The answer itself lies in her name “Lalita” which means playful. It again goes back to the concept of divine cosmic play (lila) where the Prakriti is playful and Purusha is associated with the stillness. Even Brahma Vaivarta Purana describes Radha showing the same feeling when Krishna does Rasa lila with the other Gopi. So it is nothing but the divine act of God and his power.
Did Bhagwan Shiva cheat Maa Bhavani?
Definitely not, because neither Vishnu nor the Mohini avatar is a separate entity. All the Puranas including Shiva Purana and Bhagavat Purana describe Shiva and Vishnu as completely one truth in different forms. The scriptures further described Vishnu and Parvati as the male and female forms of the same Supreme Power (Ya Uma Sa Swayam Vishnu) which means the one who is Uma is herself Vishnu or vice versa, she is described as Narayani, the female version of Narayan. Shakti herself too is described as both Shiva (Shambhu Rupini) and Vishnu (Govind Rupini)
Ardhanarishwar showing the oneness of Shiva and Shakti.
Hari Hara showing the oneness of Shiva and Vishnu.
Shiva is Vairagi while Krishna/Lalita is the playful side of the same Supreme. In fact, Devi Purana also explains it beautifully that it is not even about gender, it’s much beyond it as the Chapter 49 of Devi Purana mentions Shiva incarnating in a female form (Radha) and Parvati incarnating in a male form (Krishna).
So it is not even about Shiva being Vishnu/Krishna and Parvati being Lakshmi/Radha, it can also inter-change as it is not gender based and The Supreme Consciousness is beyond any restriction.
So it is wrongly interpreted by some people who try to find controversy in such lilas.
Shiva is described as the observer side of the Supreme while the other side is the playful aspect of the Supreme. Bhagwan Shiva sees the lilas of Maa Parvati be it her devotion or Tapasya or her playful side.
In the same way, Radharani sees the lilas of Shri Krishna playing the flute 🪈
Even in the Viyog lila or the Virah (separation act), Sati self immolated and Shiva thinks about her and goes in Samadhi.
In the exact way when Krishna goes back to Mathura, Radha misses him and always thinks about Krishna.
So it is about the meditative side of the Supreme engaging with its own playful projection and not a separate entity.
Is Shiva still worthy of devotion if he did such a thing?
Anything you worship is Shiva only, you don't even need to use the name Shiva or the specific form, you can use any name, any form or even the formless to worship the eternal truth, it's one only.
Even if you specifically talk about that one form of being worthy of devotion and worship, don't forget he is the one who consumed the deadliest Halahal Poison to save the world, it could destroyed everything.
Conclusion:
The Mohini story is nothing but Shiva’s attraction towards his own feminine side. Shiva and Mohini are not two but one essence in the actual reality.
Jai Shiv Shakti 🙏 Jai Hari Hara 🙏 Jai Radhe Krishna 🙏