Saint Isaac the Syrian Saying

Let yourself be persecuted, but do not persecute others. 
Be crucified, but do not crucify others. 
Be slandered, but do not slander others. 
Rejoice with those who rejoice, and weep with those who weep: such is the sign of purity. Suffer with the sick. 
Be afflicted with sinners. 
Exult with those who repent. 
Be the friend of all, but in your spirit remain alone. 
Be a partaker of the sufferings of all, but keep your body distant from all. 
Rebuke no one, revile no one, not even those who live very wickedly. 
Spread your cloak over those who fall into sin, each and every one, and shield them. 
And if you cannot take the fault on yourself and accept punishment in their place, do not destroy their character.

St. Isaac the Syrian

Verses and Fathers Sayings

Not that I have already attained, or am already perfected; but I press on, that I may lay hold of that for which Christ Jesus has also laid hold of me. Brethren, I do not count myself to have apprehended; but one thing I do, forgetting those things which are behind and reaching forward to those things which are ahead, I press toward the goal for the prize of the upward call of God in Christ Jesus.
Philippians 3:12-14

"Regarding every vice and every virtue, we must unceasingly scrutinize ourselves to see what point we have reached, a beginning, a middle or the end."
(If we lack any concept of setting goals and continuing to grow, we'll have no idea whether we are stuck at the beginning, complacent at the middle, or making progress toward the end.)
St. John Climacus