By “I am just human” is a more theologically-laden phrase than most using it care to acknowledge. This is where brief theological summaries are very helpful, and this is a summary of the doctrine of “Anthropology”, or in more regular terms, the study of Man.
What does the Bible say about Man?
Man is created by God in the image of God (Gen 1:27),
… and exists for God’s glory (Col 1:16; 2 Cor 5:9).
Man is dependent on God for his continual existence (Col 1:17)
… and needs God’s Word to live life successfully (Deut 8:3).
Man is conceived in sin (Ps 51:5),
… and under condemnation because of his inherent guilt (Jer 17:9; Rom 3:9-18; Heb 9:27).
Man can only be saved from the bondage of sin
… through Jesus Christ’s redemptive work (2 Cor 5:21)
… and needs the Holy Spirit to live a life pleasing to God (Rom 5:10; 1 Cor 2:14).
Man’s actions are governed
… by what he believes and desires (James 1:14-15)
… and will have to give account of his life to God who knows everything (Heb 4:13).
In essence then, the exclamation “I am just human” is a confession of “I am a sinner in desperate need of Jesus to save me from my own sinfulness so that I will live for God.”