We can be sure that we know God

only by keeping his commandments.

Anyone who says, ‘I know him’,

and does not keep his commandments,

is a liar,

refusing to admit the truth.

But when anyone does obey what he has said,

God’s love comes to perfection in him.

We can be sure that we are in God

only when the one who claims to be living in him

is living the same kind of life as Christ lived.

My dear people,

this is not a new commandment that I am writing to tell you,

but an old commandment

that you were given from the beginning,

the original commandment which was the message brought to you.

Yet in another way, what I am writing to you,

and what is being carried out in your lives as it was in his,

is a new commandment;

because the night is over

and the real light is already shining.

Anyone who claims to be in the light

but hates his brother

is still in the dark.

But anyone who loves his brother is living in the light

and need not be afraid of stumbling;

unlike the man who hates his brother and is in the darkness,

not knowing where he is going,

because it is too dark to see.