Day 1:
G‑d remembers Sarah, and gives her and Abraham a son, who is named Isaac (Yitzchak), meaning “will laugh”; Abraham is then one hundred years old, and Sarah ninety. Isaac is circumcised at the age of eight days.
Hagar and Ishmael are banished from Abraham’s home and wander in the desert; G‑d hears the cry of the dying lad, and saves his life by showing his mother a well. The Philistine king Abimelech makes a treaty with Abraham at Be’er Sheba.
Day 2:
G‑d commands Abraham to sacrifice his son on Mount Moriah (the Temple Mount) in Jerusalem. Isaac is bound and placed on the altar, and Abraham raises the knife to slaughter his son. A voice from heaven calls to stop him, saying that it was a test; a ram, caught in the undergrowth by its horns, is offered in Isaac’s place.
I once wondered if the Acada arguably constituted Maris Ayin, but concluded it did not! Our relationship with G-d is based on the ears rather than eyes. Notably, Yitzak's diminishing sight through life arguably offers the remez that the eyes must used in a very measured manner through life and not at all regarding faith in G-d. G-d is known via His back after the fact via His legacy of backing us. In effect, we satisfy His will via faithfully hearing it rather than through seeing it at the moment as we do and listen. Tellingly, despite being seeing impaired Yitzak had the midot of strength! Seeing is not believing as it relates to G-d, "B-H"! PS Shabbat Shalom and Chag Semayack Rav Shem Tov!