They are never separated

(Thomas Watson, "The Lord's Prayer")

"You were sanctified, you were justified."
    1 Corinthians 6:11

Justification and sanctification are not the same.

Justification is without us—sanctification is within us.
The one is by righteousness imputed—the other is by
righteousness imparted. Justification is once and for
all—sanctification is gradual. One person is sanctified
more than another—but one cannot be more justified
than another. One has more grace than another—but
he is not more justified than another.

The matter of our justification is perfect, namely,
Christ's righteousness; but our sanctification is
imperfect, there are the spots of God's children. Our
graces are mixed with sin, our duties are defiled.

Thus justification and sanctification are not the same.

Yet, for all that, they are never separated. God never
pardons and justifies a sinner—but He also sanctifies him.
"This is He who came by water and blood, even Jesus
Christ." 1 John 5:6. Christ comes to the soul by blood,
which denotes remission of sin; and by water, which
denotes sanctification. Let no man say he is pardoned,
who is not made holy! This I urge against those who
talk of their sin being forgiven, and having a part in
Christ—and yet remain unconverted, and live in the
grossest sins!

Where God pardons, He purifies. Whoever God forgives,
He transforms. Let no man say his sins are forgiven—who
does not find an inherent work of holiness in his heart.
"I will place My Spirit within you and cause you to follow
My statutes and carefully observe My ordinances."
Ezekiel 36:27