God rejects no one - all peoples are pleasing to Him.
Isaiah envisioned a time when foreigners would stream towards Zion, worshipping and serving in God's temple. God reads the heart. All who do what is right and seek to do His will are acceptable to him.
The temple was to be a house of prayer for all peoples. Jesus spoke of this verse when he cleansed the temple. Even Paul saw the rejection of Jesus by his people as something temporary. In the end, God's salvation was intended for all.
The Canaanite woman was not of the House of Israel, but she had great faith that Jesus could and would heal her daughter. It did not go well at first. She was rebuffed by the apostles and even by Jesus. She did not give up and even turned the statement about feeding the dogs into a witty response that won Jesus' respect. He granted her request.
The Scriptures tell us that God is not stingy with grace, compassion, mercy and love. If we claim to worship God, we cannot be either. God belongs to all.
Lord, may I share Your grace with all.