Albert Barnes Commentary John 11:15

"And I am glad for your sakes that I was not there, to the intent ye may believe; nevertheless let us go unto him." — John 11:15 (ASV)

I am glad, and so on. The meaning of this verse can be expressed as follows:

"If I had been there during his sickness, the entreaties of his sisters and friends would have prevailed with me to restore him to health. I could not have refused them without appearing to be unkind. Though a restoration to health would have been a miracle, and sufficient to convince you, yet the miracle of raising him after he had been dead for four days will be far more impressive, and on that account I rejoice that an opportunity is given in this way so strikingly to confirm your faith."

To the intent. To provide you with evidence by which you might be established in the belief that I am the Messiah.