In his famous speech at the beginning of Act II, Scene 1 of As You Like It, Duke Senior asks, "Here feel we but the penalty of Adam." He is referring to Adam in Genesis who was banished from the Garden of Eden along with Eve for eating the forbidden fruit. The Garden of Eden was a paradise in which, though naked, Adam and Eve were never cold--but part of their penalty for disobeying God was to be exposed to what Duke Senior describes as
The season's difference, as the icy fang
And churlish chiding of the winter's wind,
Which, when it bites and blows upon my body
Even till I shrink with cold, I smile and say
"This is no flattery"; these are counselors
That feelingly persuade me what I am.
When the Duke says "feel we but," he does not mean "here we do not feel" but "here do we not feel?" and "here we feel only the penalty." In the lines immediately preceding "Here feel we but the penalty of Adam," he asks
Are not these woods
More free from peril than the envious court?
So, "Here feel we but the penalty of Adam" is spoken in the same spirit, although perhaps not as a question since there is no question mark, so it might be confusing.
The quote reference is Duke Senior referring to Adam in Genesis and asking several of his loyal followers, in effect, "Do we not have to endure the cold weather, just like Adam after he was banished from the Garden of Eden, and isn't this actually beneficial, since it makes us realize how unimportant we all are and how much there is still left to us to enjoy in nature?"
What follows in this speech is one of Shakespeare's wisest and most beautiful similes:
Sweet are the uses of adversity,
Which, like the toad, ugly and venomous,
Wears yet a precious jewel in his head
The Duke is definitely not referring to the character named Adam, who is a servant of Orlando, but to the Adam of the Bible.