Of what does Jesus remind us with the words “who art in heaven”?

With the words “who art in heaven” Jesus reminds us of the truth that our heavenly Father is the Lord of all, “who can do exceeding abundantly above all that we ask or think.” Eph. 3:20.

What does Jesus teach us with the word “our”?

With the word “our” Jesus teaches that all of us who believe in Him are God’s hildren, and we pray to Him as one group, each of us supporting one another.

Gal. 3:26: For ye are all the children of God by faith in Christ Jesus.

Why does Jesus teach us to call God “Father”?

Our Father, who art in heaven. What does this mean? God would by these words tenderly invite us to believe that He is our true Father, and that we are His true children, so that we may with all boldness and confidence ask Him as dear children ask their dear father.

The word “Father” encourages us to pray with confidence, and without fear and doubt.

Rom. 8:15: For ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father.