He was always a teacher - inside the classroom and outside. For many years he enjoyed working in Oholei Torah. And for many years he enjoyed his next job at Ideal Stamps and Coins - with his wonderful Bal Habos (boss), R' Shmuel Melamed and the many other incredible people there. Even at the offices of this Manhattan workplace he was recognized by everyone as a Mashpia. He happily taught a brief Halacha or Chasidus every day during the company's Mincha break. (See below, in condolences comments and notes, for letter from the company describing his contribution to their daily learning at work.)
In his unassuming manner, he continued teaching Torah to many individua
ls and gave classes whenever requested. Here is a postcard he received from Lubavitch Youth Organization (LYO) complimenting him on the successful shiurim (Torah classes) they had heard he was giving and how pleased the participants were.
Over the years there were many individuals who recognized and appreciated the scholarly yet gentle, easy-going, and humble manner of R' Dovid, Scheiner, z"l, and asked him to learn with them on a regular basis.
Here is one class picture which reflects a lesson he had just been teaching the students about the three Patriarchs, Avraham, Yitzchok and Yaakov (Abraham, Isaac and Jacob).
They established the 3 times of the day for prayer, which is hinted to by the second letter of each of their names (which is boxed on the blackboard). "Beis" is for "boker" which means morning - thus Abraham established the morning prayer time. "Tzaddik" is for "tzaharayim" which means mid-day - for the mid-day prayer that Isaac established. "Ayin" is for "erev" translated as evening which alludes to the evening prayer time established by Jacob. (For more class photos, go to the very bottom section - "...and more photos".)