Mat 28:18 And Jesus coming, spoke to them, saying: All power is given to me in heaven and in earth.In fact, Christ's actions in Mat 15:28 demonstrate that His words in 15:24 were not meant to describe an absolute and exclusive mission, but rather a primary one. This is borne out by His final words quoted above: "all nations."
Mat 28:19 Going therefore, teach ye all nations: baptizing them in the name of the Father and of the Son and of the Holy Ghost.
Mat 28:20 Teaching them to observe all things whatsoever I have commanded you. And behold I am with you all days, even to the consummation of the world.
His ministry from the heavenly places (Ephesians; Hebrews, etc.) is not supposed to match His ministry to the lost sheep of the house of Israel conducted as the Son of Man on Earth. He is the same Lord, but He exercises different ministries.
The Church which is His Body, where there is NEITHER Jew nor Greek, NEITHER male nor female, NEITHER bond nor free, was not a subject of revelation during His earthly ministry, when He, as Israel's King, was still offering the Davidic Kingdom (Isaiah 22; etc.)to that particular Nation (which would be the ‘ekklesia’ {congregation; assembly} that He would build, and would have 12 Apostles judging 12 tribes (Matt. 19:28, NOT judging the Body of Christ - the Body of Christ is not composed of 12 or any number of tribes), at a time when He will be Personally reigning in ‘THE REGENERATION “(”THE RESTITUTION OF ALL THINGS” - ACTS 3:19-26).
Further, there is not once instance in the Book of Acts where the Apostles baptized anyone in the Name of the Father and of the Son and of the Holy Ghost. The Twelve that accompanied Christ during His earthly ministry to Israel did not have any intention to go to the nations until they saw the repentance of the Nation of Israel.
At such a time (yet future to us), when Israel does repent (and they will(!), as a Nation), 12,000 evangelists from each of the 12 tribes will go to the nations (Rev. chs. 7, 14), and they will baptize in the name of the Father and of the Son and of the Holy Ghost.
Neither John, nor the 12 Apostles, nor the Seventy, Nor Paul, nor anyone in the New Testament ever sprinkled or put water on the heads of infants, calling it baptism.