Matthew 10:42 contains an almost identical promise about a cup of cold water in Jesus' name, reinforcing the reward for hospitality to His followers.

Matthew 18:5 promises reward for receiving a child in Jesus' name — directly parallel to giving water for Christ's sake.

In Matthew 25:40, Jesus identifies with the least, teaching that serving them is serving Him—expanding Mark's reward for giving a cup to believers.

2 Samuel 9:1 shows David seeking kindness for Jonathan's sake — analogous to giving water for Christ's sake in Mark.

2 Kings 4:10 recounts hospitality for Elisha — similar to offering a cup of water for a disciple because of Christ.

In Romans 8:9, belonging to Christ is defined by having the Spirit—clarifying the identity of those who receive the cup in Mark 9:41.

In Hebrews 6:10, God remembers work and love shown for his name, echoing the promise that a cup of water given for Christ will be rewarded.