Zera Shimshon .... Va'Yeirah

(כי שמע אלקים אל קול הנער באשר הוא שם ( כא' יז 

For Hashem has heard the voice of the lad as he is (21:17) 

Rashi explains that although the angels were trying to have Yishma'el die in his illness on account of his future actions, namely that his descendants would torture the Jews to death (see Rashi for details). Hashem countered their claim and said that since at this point he is still righteous he is judged as he is at this point in time. 




This we find happened as well when the Jewish people left Egypt, although Hashem knew that the Jewish people would sin and worship the golden calf, Hashem did not hesitate to redeem and give the gold that would eventfully be used to create the golden calf since Hashem deals with the people based on their deeds at the present. 

The Medrash adds (Shemos Rabba 1:36) 
that although Hashem knew the Jews would sin with the golden calf, He also knew that they would proclaim ונשמע נעשה" ,We will do and we will accept", when asked if they want to accept the Torah. 

On this the Prashas Derachim writes (Derech Mitzrayim §4) that from here we see the extent of Hashem's kindness for although the Jews would do good (ונשמע נעשה (and also bad (the golden calf), nevertheless, Hashem does not hold back the good for their future actions (taking the Jews out of Egypt on account of their accepting the Torah) in face of their future sins (the golden calf). 

The Zera Shimshon asks - 
since Hashem is entirely just, if strict justice says that a person is judged based on his present situation, and any future bad actions never affects how the person is dealt with today, why then does he take into account the future good actions? 

The Zera Shimshon explains 
that strict justice dictates that a person is dealt with according to his present actions. However, every individual has a mission in this world to rectify something that no one else can rectify. When a person accomplishes this mission it is irreversible - the rectification that he did in the higher worlds exists forever. 

In addition, once this rectification is done it brings Mashiach one step closer. 
When a person sins however, with repentance the sin can be erased as if it was never done. 

Therefore, regarding the future good that a person will do, since it is everlasting, Hashem is willing to take it into account. Whereas the bad actions are not everlasting and can be erased with teshuva, they therefore are only dealt with when they actually happen.