MATT 7: 17 Even so, every good tree bears good fruit, but a bad tree bears bad fruit. 18 A good tree cannot bear bad fruit, nor can a bad tree bear good fruit.19 Every tree that does not bear good fruit is cut down and thrown into the fire. 20 Therefore by their fruits you will know them.
When I see someone with peace, joy, long sufferance, patience, love, etc., I recognize their relationship with Christ. And someone who does not have these fruits has probably not given themselves to him. The fruits come from a place of total surrender. That is when the Holy Spirit's fruits can be seen.