Little Lamb, who made thee?
Dost thou know who made thee?
Gave thee life, and bid thee feed
By the stream and o'er the mead;
Gave thee clothing of delight
Softest clothing, woolly, bright;
Gave thee such a tender voice
Lambs are traditionally seen as followers in need of a shepherd. The specificities within the speaker’s question (which has now been asked three times) imply that the lamb is wholly dependent on some greater power. 
 The ‘stream’ is a reference to the Christian tradition, in which water symbolises purity and baptism — a commitment to God.   Consequently, bidding the lamb to feed by water reflects its purity and innocence.
The Lamb