not at all, but let your yea be
yea, and your nay nay." That is Christianity. And that which is the
essential peculiarity of this Christianity lies in these two things.
First of all, that the morality which it teaches is _disinterested_
goodness--goodness not for the sake of the blessing that follows it,
but for its own sake, and because it is right. "Love your enemies," is
the Gospel precept. Why?--Because if you love them you shall be
blessed; and if you do not cursed? No; but "Love your enemies, bless
them that curse you, do good to them that hate you, and pray for them
which despitefully use you and persecute you, that ye may be the
children of"--that is, may be like--"your Father which is in Heaven."
The second essential peculiarity of Christianity--and this, too, is an
essential peculiarity of this Sermon--is, that it teaches and enforces
the law of self-sacrifice. "If thy right eye offend thee pluck it out;
if thy right hand offend thee cut it off." This, brethren, is the law
of self-sacrifice--the very law and spirit of the blessed cross of
Christ.

How deeply and essentially Christian, then, this Sermon on the Mount
is, we shall understand if we are enabled in any measure to reach the
meaning and spirit of the single passage which I have taken as my
text. It tells two things--the Christian aim and the Christian motive.

1st. The Christian aim--perfection. 2nd. The Christian
motive--because it is right and Godlike to be perfect.

I. The Christian aim is this--to be perfect. "Be ye therefore
perfect." Now distinguish this, I pray you, from mere worldly
morality. It is not conformity to a creed that is here required, but
aspiration after a _state_. It is not demanded of us to perform a
number of duties, but to yield obedience to a certain spiritual law.
But let us endeavour to explain this more fully. What is the meaning
of this expression, "Be ye perfect?" Why is it that in this discourse,
instead of being commanded to perform religious duties, we are
commanded to think of being like God? Will not that inflame our pride,
and increase our natural vainglory? Now the nature and possibility of
human perfection, what it is and how it is possible, are both
contained in one single expression in the text. "Even as your Father
which is in Heaven is perfect." The relationship between father and
son implies consanguinity, likeness, similarity of character and
nature. God _made_ the i