Sanctification of the Spirit is certainly a prerequisite to loving one another.
1 Peter 1:
22 Since you have purified your souls in obeying the truth through the Spirit in sincere love of the brethren, love one another fervently with a pure heart,
23 having been born again, not of corruptible seed but incorruptible, through the word of God which lives and abides forever,
24 because
All flesh is as grass,
And all the glory of man as the flower of the grass.
The grass withers,
And its flower falls away,
25 But the word of the Lord endures forever.
Now this is the word which by the gospel was preached to you.
Fellowship with one another in the Spirit is to "wash one another".
1 John 1:7 But if we walk in the light as He is in the light, we have fellowship with one another,
and the blood of Jesus Christ His Son cleanses us from all sin.
John 15:
12 This is My commandment, that you love one another as I have loved you.
13 Greater love has no one than this, than to lay down one’s life for his friends.