Can we ask him that, what would be his rationale to say that?

Any rational human being is capable of articulating truth. And I assume your friend is, this is why we should asked for his rationale.

Precisely. This is why I said "any"... not all humans are rational.

I am not child expert and I cannot assert regarding their rationality. But I know children are inconsistent decision makers. However, a child at early age is not strong enough to resist or oppose the will of his parents - customs and upbringing.

We have discussed this with you before here that every child is born in a state Fitra. That means, every baby when born has recognition of God. As a part of their nature, a Creator imprinted in the soul. It is the parents who make that child a Jew or a Christian or a Polytheist or Atheist. Naturally, a child submits to physical laws of universe, the soul submits naturally to the fact that God is his Lord and Creator. But, the parents try to make him follow their own way (read religion). And a child at that early age is not strong enough to resist or oppose the will of his parents - customs and upbringing.

I did not say rationality equates opposition.

You asked about children. You see, every child is born in a state Fitra. It is the parents who make that child a Jew or a Christian or a Polytheist or Atheist and a child gets brainwashed into the customs and upbringing of the environment.

Now when you reach adulthood, you need to use your mind, INVESTIGATE, why should you be blind to something that might have impact on your life and come into your own conclusion.

This applies to almost everything. From career, to matters of faith. As an adult you need to begin to rationalize your choices in life.

So why bother asking "what has qualified him to say so?"

So what about his non trivial claim?

Believe in God is not blind faith. Talk for Islam, it calls us to reason and ponder about the signs and evidences.

Surah Baqarah 2:21 says O mankind! Worship your Lord, Who created you and those who were before you... 22 Who has made the earth as a resting place for you, and the sky as canopy, and sent down water (rain) from the sky and brought forth therewith fruits as a provision for you. Then do you not set up rivals to God (in worship) while you know.

Verily, in the creation of the heavens and the earth, and in the alteration of night and day, and the ships which sail through the sea with that which is of use to mankind, and the water (rain) which God sends down from the sky and makes the earth alive therewith after its death, and the moving (living) creatures of all kinds that He has scattered therein, and in the veering winds and clouds which are held between the sky and the earth are indeed ayats (universal proofs, evidences, signs, etc) for people of understanding Quran surah Baqarah chapter 2:164.

https://www.youtube.com/watch?v=JI24GM28QLs

We could be ONE people.....Muslims and Christians, whether we believe it not, the noble Quran, Holy Bible seem to point to something... we need to read both books with an open mind before we choose sides out of ignorance of the other side..

I am on surah 3. Al_Imran, reading under the radar looking forward to what I can find