“עַל כֵּן לֹא יָקֻמוּ רְשָׁעִים בַּמִּשְׁפָּט וְחַטָּאִים בַּעֲדַת צַדִּיקִים“

“Therefore, the wicked shall not stand up in judgment, nor shall the sinners in the congregation of the righteous.“

Wicked`s sentence will come. But why is does it happen that way?

Why won’t the punishment be an immediate one? so we can witness it, the wicked themselves will see the righteousness of the Lord and everyone therefor improve their ways?

The possibility to worship G-d with free will!
Without the hindrance of the punishment, there isn’t a real option for one to sin.. no option to to worship the Lord out of pure free will.

Give it a try, offer a kid two option:
1 – eat a candy and you will hit him to death with a terrible stick you hold in your hand,
..Or..
2 – eat a carrot, and he’ll get a bag full of colorful candies you hold in the other hand…

The opportunity to worship HaShem purely out of free will, is given only when outcome is concealed, not immediate.