Contradiction with Matthew 28:19-20
Mark 7:24 says Jesus wanted to keep his presence secret, whereas Matthew 28:19-20 commands believers to spread His teachings to all nations.
Matthew 28:19-20: Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: [teach...: or, make disciples, or, Christians of all nations]
Contradiction with Luke 8:16
Mark 7:24 depicts Jesus seeking privacy, while Luke 8:16 emphasizes not hiding one's light, implying openness.
Luke 8:16: No man, when he hath lighted a candle, covereth it with a vessel, or putteth [it] under a bed; but setteth [it] on a candlestick, that they which enter in may see the light.
Contradiction with John 18:20
Mark 7:24 shows Jesus wanting to be hidden, while in John 18:20, He states that He spoke openly to the world.
John 18:20: Jesus answered him, I spake openly to the world; I ever taught in the synagogue, and in the temple, whither the Jews always resort; and in secret have I said nothing.