And this I pray, that your love may abound yet more and more in knowledge and [in] all judgment;
Note 11 at Php 1:9: As Peter so aptly put it in 2Pe 1:3, "his divine power hath given unto us all things that pertain unto life and godliness, through the knowledge of him." Even love is based on knowledge. Our love can be increased with the correct knowledge and diminished with the wrong knowledge.
We have all experienced an increased love for someone as we learn of some special thing that person has done for us. Likewise, we have all experienced a loss of love when we have discovered things that someone we love has done to hurt us. Our knowledge influences our emotions. The more we know of God and His ways, the more our love for God and others will abound.
Note 12 at Php 1:9: The knowledge that is being spoken of here is spiritual understanding of God's love. Judgment is the ability to use or apply that knowledge correctly. Paul was saying that as we gain spiritual understanding of God's love and learn to apply it correctly in our relationships, then the manifestation of God's love in our lives will increase dramatically.