What do we learn from "Lehanchil Ohavai Yesh [v'Otzeroseihem Amalei]"?
Avos (5:19): Talmidim of Avraham eat 1 in this world, and inherit the world to come.
Sanhedrin 100a 2 : In the future, Hashem will give every Tzadik 310 worlds (the Gematri'a of Yesh). Therefore, Tzadikim will be able to receive His 'handfuls' of good ("Baruch Hashem Yom Yom Ya'amas Lanu" - Ya'amas hints to Umso (His handfuls)), even though "v'Shamayim ba'Zeres Tiken" (His hand spans Shamayim).
Rashi: Yesh (there is with Me) a great inheritance [to bestow to My lovers].
Malbim: I am prepared to bestow to My lovers Yesh - the fruits of their virtue. The merit exists. It itself prepared the reward of their virtue - "Ki Pri Ma'aleleihem Yochelu" (Yeshayah 3:10). This reward truly exists, unlike worldly follies, which are nothing.
Why does it add "v'Otzeroseihem Amalei]"?
Malbim: In addition to the Yesh prepared for them via Mishpat, I will give to them dear gifts via supreme Tzedakah.