When you define a from tween, GSAP will set your element to that position and animate back to original position. So for example if your element is at 0 and you create a from tween with value of 100, GSAP will set your element to 100 and animate back to 0. If while creating the tween if element was at 50, then GSAP will animate from 100 to 50. If it was already at 100, then nothing will happen because start and end positions are same.
I removed each because it was unnecessary. You can still use each and it will work.
Also, with GSAP you don't need anything like jQuery's stop. GSAP overwrites any tweens for same property of the element by default. You can change the overwrite behavior if you ever need, check the docs. https://greensock.com/docs/TweenLite
You can visit the learning page and youtube channel to get familiar with GSAP API,
https://greensock.com/learning
https://www.youtube.com/user/GreenSockLearning