Our Parasha, Vayiqra, opens a new sefer with the following verses:
1 Hashem called to Moses and spoke to him from the Tent of Meeting. He said, 2 "Speak to the Israelites and say to them: 'When any of you brings an offering to Hashem, bring as your offering an animal from either the herd or the flock."
Many commentators ask why there is a repetition in the first verse, as it reads "Hashem called" and then "spoke". However, based upon the Talmoud in Masechet Yoma, we can learn a fantastic lesson especially this week of Parashat Zachor, which we read as well.
The Gemara states that Hashem first called to Moshe and then spoke to teach us a lesson, that a person should not start speaking to his friend until he first calls to him. The rationale behind this practice is simple. Once being called, the friend knows to pay attention and listen to the individual speaking, and avoid and miscommunications.
It is a simple lesson that is being taught on a grand scale.
What is the harm in simply speaking directly to one's friend without calling to him or her in advance?
Doing so exhibits a behavior that is rash and non-balanced. In Masechet Niddah, the Gemara relates that Hashem "hates" all those who walk unexpectedly into their friend's home. In Masechet Derech Eretz written by the Geonim, we are told to learn from Hashem, who stood outside the Garden of Eden and called to Adam, before He entered the garden.
So too here, a person should show respect and manners in his conduct with his fellow man. Unlike Amaleq- After the regular reading from the Torah, we read how Amaleq attacked Bnei Yisrael. The verse states "Asher Qaricha" which translates as "Who came unexpectedly". One of the first wrong doings that Amaleq was guilty of was coming at the nation unexpectedly. They attacked the nation in a way that must never be forgotten.
We learn from the beginning of our Torah portion, all the way to the end, that one must be careful in his approach with his fellow neighbor, even to the point of calling out his or her name before speaking – Kal vahomer in dealings of business, property disputes and so forth.