Some argue that the Bible is contradictory concerning who asked Jesus if James and John could sit beside Jesus in his kingdom. The argument is that Matthew 20:20-21 says that the mother asked Jesus, but Mark 20:35-37 says that James and John asked Jesus. However, there is a reasonable explanation that solves this alleged contradiction in the Bible.
35 And James and John, the sons of Zebedee, came up to him and said to him, “Teacher, we want you to do for us whatever we ask of you.” 36 And he said to them, “What do you want me to do for you?” 37 And they said to him, “Grant us to sit, one at your right hand and one at your left, in your glory.”
Mark 10:35-37
20 Then the mother of the sons of Zebedee came up to him with her sons, and kneeling before him she asked him for something. 21 And he said to her, “What do you want?” She said to him, “Say that these two sons of mine are to sit, one at your right hand and one at your left, in your kingdom.”
Matthew 20:20-21
It is reasonable to believe that there were two separate occasions where this question was asked to Jesus. First, the mother asked Jesus, and then sometime later, James and John asked Jesus. The two events are not mutually exclusive.
There are some foundational principles that apply to all alleged and apparent contradictions in the Bible. To read more, see Bible Difficulties: Foundational Principles.
To read more answers to alleged and apparent contradictions in the Bible, see “Contradictions” in the Bible Answered.
These books are also excellent resources:
Evidence That Demands a Verdict: Life-Changing Truth for a Skeptical World - Josh and Sean McDowell
Little Pilgrim's Progress (Illustrated Edition) - Helen L. Taylor