He was human. Of course he had a temper. He was a creature instilled with emotions just as is every person. Even Jesus Christ who was half human half deity while on Earth had a temper at times. And it doesn't stop at humankind, God in Heaven has a temper and we are made in his image. So, I have no doubt that good ole Abe had his good side and his not so good side. Its just all part of living and being real.
There was also a practical reason for getting his charges well and truly lost - making it harder for their erstwhile captors to find them and lead them back to captivity.
LOL! You are so right about it being Moses, and I never noticed even while I was replying. Thanx for pointing that out. I should pay closer attention sometimes.