strong, and may mar youthful purity. So, taking all these into
account, I have thought that I could not do better than press home upon
you the counsels of this magnificent text, however inadequately my time
may permit of my dealing with them; for there are dozens of sermons in
it, if one could expand it worthily.

But my purpose is distinctly practical, and so I wish just to cast what
I have to say to you into the answer to three questions, the three
questions that may be asked about everything. What? Why? How?

I. _What_, then, is the counsel here?

'Think on these things.' To begin with, that advice implies that we can,
and, therefore, that we should, exercise a very rigid control over that
part of our lives which a great many of us never think of controlling at
all. There are hosts of people whose thoughts are just hooked on to one
another by the slightest links of accidental connection, and who
scarcely ever have put a strong hand upon them, or coerced them into
order, or decided what they are going to let come into their minds, and
what to keep out. Circumstances, the necessities of our daily
occupations, the duties that we owe to one another, all these make
certain streams of thought very necessary, and to some of us very
absorbing. And for the rest--well! 'He that hath no rule over his own
spirit is like a city broken down, without walls'; anybody can go in,
and anybody can come out. I am sure that amongst young men and women
there are multitudes who have never realised how responsible they are
for the flow of the waves of that great river that is always coming from
the depths of their being, and have never asked whether the current is
bringing down sand or gold. Exercise control, as becomes you, over the
run and drift of your thoughts. I said that many of us had minds like
cities broken down. Put a guard at the gate, as they do in some
Continental countries, and let in no vagrant that cannot show his
passport, and a clear bill of health. Now, that is a lesson that some of
you very much want.

But, further, notice that company of fair guests that you may welcome
into the hospitalities of your heart and mind. 'Think on these
things'--and what are they? It would be absurd of me to try to exhaust
the great catalogue which the Apostle gives here, but let me say a word
or two about it.

'Whatsoever things are true . . . think on these things.' Let your minds
be exercised, breathed, braced, lifted, filled by brin