the tale of the silent alif in انا

There are already four places in the language where hamza and nun couple together:
اِنَّ اِنْ اَنْ اَنَّ

All four are used in different ways:

اَنْ - converts the مضاري verb into a مصدر and occurs in the middle of a sentence
اِنْ is for conditional, it's followed by two مضاري verbs, in the context of condition and reward/ consequence. For example, IF Zaid comes to you, honour him.

اِنَّ and اَنَّ are called حرف مشبه بلفيل Translated as indeed, they have a subject and predicate coming after it.

اِنَّ comes at the beginning of the sentence, followed by an ism.
اَنَّ comes in the middle of a sentence and followed by an ism

So, in a book without vowels if you see a hamza followed by a nun, based on what comes after it, you can distinguish the one from the other.

But fifth instance of hamza and nun ( انا ) -can be followed by a noun or a verb. And you won't be able to tell it's the pronoun. The silent alif was added at the end- to make a profound difference.

“Alhamdulillah”

Nouman Ali Khan of Al Bayyinah Institute write:

A Variety of Ways to Make Hamd of Allah

Arabic offers great flexibility in communication. There are varying degrees of emphasis with which a statement can be made. There are multiple options that can be manipulated in sentence structure. Similar statements can be made such as :

أحمدُ اللهَ

“I praise Allah.”
نَحْمَدُ اللهَ

“We praise Allah.”

اِحْمَدُوْا اللهَ

“Praise Allah!”.

1. All of the above are Jumal Fi’liyyah. This sentence structure necessarily implies the occurrence of an act bound by time. Alhamdu Lillah is Jumlah Ismiyyah which, for one, is a far more emphatic form of declaration in Classical Arabic by comparison. Secondly, it implies continuity, stability and permanence. Another unique feature of the Ismiyyah structure is that it communicates a decisive statement.

2. Jumlah Fi’liyyah exclusively attributes an act to a specific subject. In the suggested alternatives above, ‘I’, ‘we’ and ‘you all’ are the specific subjects respectively. الحمد لله , being a Jumlah Ismiyyah, doesn’t identify the subject which makes it a universal declaration. I, we, you, they, people, animals, rocks, trees, rather all of creation can be understood as the subject! There is another beautiful subtlety here. Whether anyone or anything makes حمد of Allah or not, الحمد is still for Allah!

3. The Jumlah Fi’liyyah renditions above are limited by time and applicability. The original statement is timeless and has universal applicability. Through الحمد للهِ the way in which the praise is made is kept unspecified while in the Fi’liyyah format the praise would be by the tongue.

وَإنْ مِنْ شَيْئٍ إلا يُسَبِّحُ بِحَمْدِهِ ولكِنْ لا تَفْقَهُوْنَ تَسْبِيْحَهُمْ

4. In Jumlah Fi’liyyah there is the possibility of doing an act for an object that isn’t worthy of it. For instance, ‘I paid him’. It may be that ‘he’ didn’t deserve to get paid. In Jumlah Ismiyyah the necessary implication that this praise is actually rightfully placed is naturally implied, ALHAMDULILLAH!

5. In saying الحمد لله , we are also acknowledging that حمد is the property of Allah while this is not implied in alternative fi’liyyah renditions. When using the command form, ’Praise Allah’ instead of Alhamdulillah, there are a number of shortcomings. Firstly, there is the sense that this praise is being asked of the audience. By comparison الحمد لله declares the existence of حمد without dependence on an audience responding to an imperative. The imperative may also imply a response that may or may not be voluntary while Alhamdulillah is an observation of the voluntary praise done by all forms of creation.

Quoted from “Alhamdulillah” - A Linguistic Miracle of the Quran