I am always learning new things about people I already know. You think you know somebody well? I promise you that there are aspects of this person with which you are not familiar [and maybe even he is not]. The soul of man is so deep! It is nothing less than fascinating to plumb the depths of someone's soul. When you do this it enables you to connect, appreciate and ultimately come closer to this person.
Torah is the same way. You can see the same source a THOUSAND times and then hear or think of a brand new insight that never occured to you. That is what the gemara in brachos means "Im shamoa biyashan tishmi'u bichadash" -if you constantly review the old you will see the new.
Many years ago a seminary girl was in my house and she said to me something to the effect of "Aren't you bored with torah already?! Don't you want to go to university and study exciting new material?"
Sweet young friend - no. I am not, and will never be, bored with torah.
"TORAS HASHEM TEMIMA MESHIVAS NEFESH AIDUS HASHEM NEEMANA MACHKIMAS PESI."