The case is similar to a Muslim who has a dream where he is told to do worship an idol. The dreamer has no surety that the dream is a command from God, and indeed it goes against what is certainly the command of Allah (to not commit shirk) ... in all likelihood the dream is a trick from the devil to misguide the dreamer.
Comparing oneself to Abraham is a fallacy. Abraham was a Prophet, a man so close to God that God called him His friend (Khalil Ullah)[4:125]. The dreams of Prophets are always true and are a form of revelation.
Tafsir Ibn Kathir on 37:102
Ubayd bin `Umayr said, "The dreams of the Prophets are revelation".
Tafsir Al Qurtubi on 37:102
قال مقاتل: رأى ذلك إبراهيم عليه السلام ثلاث ليال متتابعات. وقال محمد
بن كعب: كانت الرسل يأتيهم الوحي من اللّه تعالى أيقاظاً ورقوداً، فإن
الأنبياء لا تنام قلوبهم. وهذا ثابت في الخبر المرفوع، قال صلى الله عليه
وسلم: " إنا معاشر الأنبياء تنام أعيننا ولا تنام قلوبنا " وقال ٱبن
عباس: رؤيا الأنبياء وَحْيٌ وٱستدل بهذه الآية. وقال السّدي: لما بُشِّر
إبراهيم بإسحاق قبل أن يولد قال هو إذاً لله ذبيح. فقيل له في منامه: قد
نذرت نذراً فَفِ بنذرك.
Muqatil said: "Abraham dreamt three consecutive nights." Muhammad bin
Ka'ab said: "Allah sends revelations to Prophets while they are awake
and while they sleep, because the Prophet's hearts don't sleep." It is
proven in Hadith that the Prophet said: "Us Prophets, our eyes sleep
but hearts do not". Ibn Abbas said: "The Prophets' dreams are
revelation" and he pointed to this verse. Sadi said: "When Abraham was
informed of the glad tidings of Isaac's birth, Abraham said: "He is
sacrificed for Allah.", then it was told to him in a dream: "You
Vowed, so fulfill your vow".
Even if it had been a mistake on Abraham's part, a revelation would have been sent to correct him (we see several examples of such in the life of the Prophet Muhammad(p.b.u.h) in the Quran, for example 66:1, 80:1, 33:37). Instead, we have angels aiding him as recorded in a tradition narrated in Tafsir Ibn Kathir:
Then Jibril(Gabriel), upon him be peace, took him to Jamrat Al-`Aqabah
and the Shaytan appeared to him, so he stoned him with seven pebbles
until he disappeared. Then he appeared him at Al-Jamrah Al-Wusta and
he stoned him with seven pebbles.
From Tafsir Al Qurtubi:
وروي أنه لما ذبحه قال جبريل: اللّه أكبر اللّه أكبر. فقال الذبيح: لا
إلٰه إلا اللّه واللّه أكبر. فقال إبراهيم: اللّه أكبر والحمد للّه؛ فبقي
It is narrated that when Abraham was about to perform the sacrifice,
Gabriel said: "Allah is Great, Allah is Great", on this
Zabih-Ullah(Ishmael) said: "There is no god except Allah, and Allah is
Great" and on this Abraham said "Allah is Great and all praise is for
Allah", and so this takbeer became the Sunnah.
A common person does not receive revelation (indeed revelation has ceased with Prophethood), and they don't see and interact with angels. The dreams of a common person can be from three sources, (i) from God, (ii) from the devil, (iii) from the thinking of their own mind (hadith 1,2,3,4), the source is not certain.
“A man came to the Prophet (ﷺ) when he was delivering a sermon and
said: ‘O Messenger of Allah! Last night in my dream I saw my neck
being struck and my head fell off, and I chased it, picked it up and
put it back.’ The Messenger of Allah (ﷺ) said: ‘If Satan plays with
any one of you in his dreams, he should not tell people about it.’”
On the other hand, what is certain is that killing an innocent is forbidden and a major sin.
Quran 17:33 And do not kill the soul which Allah has forbidden,
except by right. And whoever is killed unjustly - We have given his
heir authority, but let him not exceed limits in [the matter of]
taking life. Indeed, he has been supported [by the law].
Quran 4:29 O you who have believed, do not consume one another's
wealth unjustly but only [in lawful] business by mutual consent. And
do not kill yourselves [i.e one another]. Indeed, Allah is to you ever
Quran 5:32 Because of that, We decreed upon the Children of
Israel that whoever kills a soul unless for a soul or for corruption
[done] in the land - it is as if he had slain mankind entirely. And
whoever saves one - it is as if he had saved mankind entirely. And our
messengers had certainly come to them with clear proofs. Then indeed
many of them, [even] after that, throughout the land, were
Also it is certain that God has enjoined a proper method of sacrifice, i.e. it should be an anam animal (cattle). And it is certain that Allah didn't intend for a human sacrifice and substituted it for a lamb in Abraham's case.
So, if a modern day muslim is to have a dream about sacrificing his child, he should act on what is certain and ignore the dream. Indeed acting on the dream would be disobedience to Allah.