3 We are bound to always give thanks to God for you, brothers, even as it is appropriate, because your faith grows exceedingly, and the love of each and every one of you towards one another abounds (WEB)
“We are bound to always give thanks to God for you, brothers” This verse brings to mind 1 Samuel 12:23 which says, “Moreover as for me, far be it from me that I should sin against Yahweh in ceasing to pray for you: but I will instruct you in the good and the right way.”
Just like Samuel who felt that he would be sinning if he would not pray for God’s people, likewise we are bound to those that Jesus has put in our lives [brothers in Jesus Christ] to always pray for them.
“We are bound” implies a conviction from the Holy Spirit to look after our brothers in Christ Jesus through prayer for their good and perseverance in the faith.
“because your faith grows exceedingly” Paul sees the faith of the church in Thessalonica growing strong, due to the love that they are expressing.
Jesus said in the Book of John that the way people outside the faith [the world] will know that we are Christians and stand out from everyone else is by loving not only our neighbors but, those who go against us.
“By this everyone will know that you are my disciples, if you have love for one another.” (WEB)