In case and peace, whilst your brethren are engaged in a bloody war. Their words were ambiguous, and Moses thought this to be an act of unbelief and sloth and self-love and policy.
Related Commentaries of Numbers 32:6
Numbers 32:6
6 And Moses said unto the children of Gad and to the children of Reuben, Shall your brethren go to war, and shall ye sit here?