So God created man in his own image, in the image of God he created him; male and female he created them.
― Genesis 1:27 (ESV)
While we say, we are one world and one earth, we have raging battles on the basis of skin colors. There's yellow skin, white skin, black skin, brown skin, red skin, and God knows which all the skin types are that we come across from different ethnic backgrounds. We have torn the world apart by what we know as racial discrimination. There is no dearth of examples, wherein an innocent life has been lost due to raging fights owing to color, cast, and creed.
We hear of leaders emerging every now and then to fight for equal rights for the suppressed, albeit the cry dies a slow death almost every time. What I have learned since childhood has been that God created mankind in his own image and likeness. Which just goes to show that God considers all of us as equals in His eyes. When we believe God is just and kind, He is surely not going to discriminate between any of His beloved children.
For just as the body is one and has many members, and all the members of the body, though many, are one body, so it is with Christ. For in one Spirit we were all baptized into one body-Jews or Greeks, slaves or free-and all were made to drink of one Spirit.
― 1 Corinthians 12:12-13 (ESV)
The Bible is pretty clear when it states that we might have our differences, but in the end, we are all equals. In God's eyes, we all become one flesh and blood, and the best part is that we are all brought together with the blood of Jesus that baptizes us in one Spirit. In God's eyes, there is definitely no discrimination based on color, creed, or race. When God showers his blessings, he doesn't look at whether you are a Jew, Caucasian, African, Asian, Indian, or Arab. Romans 2:11 and 10:12 resound the theme that God is not partial and does not differentiate between anyone who calls on him.
There is neither Jew nor Greek, there is neither slave nor free, there is no male and female, for you are all one in Christ Jesus.
― Galatians 3:28 (ESV)
Isn't this proof enough that there's just one human race that encompasses the whole world? The Bible commands us to treat everyone as equal without partiality because our master in heaven is not partial. In Ephesians 6:9 and Acts 10:34-35, we are reminded of God's impartial love and mercy. Far from being partial, in 1 Samuel 16:7, we understand that it is we who look at the outward appearance, while God peers at what is inside.
But he,desiring to justify himself, said to Jesus, "And who is my neighbor?...
... He said, "The one who showed him mercy." And Jesus said to him,"You go, and do likewise."
― Luke 10:29, 37 (ESV)
The Bible says, ask not who is sitting next to you, but instead, continue doing good. On the other hand, in Ephesians 2, we are told that Christ with the sacrifice of His life has united all that was earlier divided. This further implies that we aren't really meant to be divided, but united in Christ, and therefore, one in Spirit. Making peace with our brethren is the call of the day, rather than discriminating and being biased.
A new commandment I give to you, that you love one another: just as I have loved you, you also are to love one another.
― John 13:34 (ESV)
As Christians, we are called to overlook our neighbor's shortcomings; instead, we are called to love like Christ loved us all. We are called not to judge one another, but to surrender our lives in serving one another. The Bible says that, as Christ's followers, we ought to do unto others as we would want to be done to ourselves.
Summing it up, the Bible tells us to respect one another because we are one in Christ, and hence, one in the Father who has created us. We also ought to love one another and reach out to our fellow beings, as Christ himself loved and reached out to the people around him. So to say, we are one, one body in Jesus, and this one body should not be divided, lest we divide the Body of Christ himself.