Instant Gratification

وَالسَّابِقُونَ الْأَوَّلُونَ مِنَ الْمُهَاجِرِينَ وَالْأَنصَارِ وَالَّذِينَ اتَّبَعُوهُم بِإِحْسَانٍ رَّضِيَ اللَّهُ عَنْهُمْ وَرَضُوا عَنْهُ وَأَعَدَّ لَهُمْ جَنَّاتٍ تَجْرِي تَحْتَهَا الْأَنْهَارُ خَالِدِينَ فِيهَا أَبَدًا ذَٰلِكَ الْفَوْزُ الْعَظِيمُ

And the first to embrace Islam of the Muhajirun (those who migrated from Makkah to Al-Madinah) and the Ansar (the citizens of Al-Madinah who helped and gave aid to the Muhajirun) and also those who followed them exactly (in Faith). Allah is well-pleased with them as they are well-pleased with Him. He has prepared for them Gardens under which rivers flow (Paradise), to dwell therein forever. That is the supreme success.

This is verse 100 in Surah Altawba.

Throughout the entire Quran, When Allah describes jannah to the believers, it always says
"جنات تجري من تحتها/تحتهم الأنهار".
"Gardens under which FROM IT rivers flow''.

However, there is
only one verse (this one) that I found

من that does not use
and instead He says
"جنات تجري تحتها الأنهار ".
"Gardens under which rivers flow"

In Arabic Grammar, I took the case called منصوب على نزع الخافض
and I thought this could be the case. So the
من is implied
Whether that is the case or not, it is interesting that from about 40 instances where Jannah is described, only this one does not have من.
In looking at what the verse is talking about, it refers to the saabiqoon and awwaloon of the muhajireen and Ansaar, so they were the first to give up everything for Allah's sake. The first to give up their homes, their lifestyle, their everything for Islam. And because of their immediate sacrifice, Allah rewards them a by not putting the word من,
so that way it makes their reward more instant, preceding everyone else's reward. Something we know to be as instant gratification.
Not only that, but looking at it in more depth, the lack of
من also
gives an implication that the rivers under this garden are more abundant.
All these meanings from just removing one two-letter word. Tell me that's not mind blowing!