I never cease to be amazed at how many ways the aspects of Christian and Islamic theology can be contrasted. For example, in each religion, often the very same symbol is used as an illustration. For example, Jesus uses the mustard seed to illustrate a point in the Bible. Similarly, the Qur’an uses the mustard seed to illustrate a point in the Qur’an. Yet the very same item is used as an avenue to illustrate two drastically opposing concepts.
In the Bible, there are two parables that use a mustard seed to make a point. One of them occurs in Matthew 13 and regards the growth and expansion of the kingdom of heaven. The other, which we will examine in more detail, occurs in Matthew 17. To put the parable in context, Jesus has just transfigured himself, and He and the disciples have come down from the mountain where they meet a man whose son is demon possessed (Matthew 17:15). The man had already been in contact with Jesus’ disciples, who were unable to do anything about it (Matthew 17:16). Jesus heals the boy (Matthew 17:18) and it is here where the story picks up in verse 19,
19 Then the disciples came to Jesus privately and said, “Why could we not drive it out?” 20 And He said to them, “Because of the littleness of your faith; for truly I say to you, if you have faith the size of a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible to you.
The issue at hand is faith. How much faith must you have? According to Jesus, the amount of faith required to accomplish the seemingly impossible is tiny. The mustard seed is used as this illustration because of its miniscule size. It takes the smallest amount of faith in order to connect with God and subsequently perform good works. God also makes it clear in the Bible that it is faith alone which leads to salvation (Ephesians 2:8-9). The result of even the tiniest amount of faith is not just the path to salvation, but the power of God to then tap into His power (Ephesians 2:10). While Jesus’ parable doesn’t explicitly refer to salvation, it is about faith, and how much you are required to have. The point is that the mustard seed is used as a measure of faith, which is what leads to salvation, which is what later leads to good works.
The Qur’an also mentions the mustard seed. This verse in the Qur’an references salvation more directly. It specifically tells the Muslim faithful about the accuracy of measurement when their deeds are weighed and their eternal destiny will be determined.
[21.47] And We will set up a just balance on the day of resurrection, so no soul shall be dealt with unjustly in the least; and though there be the weight of a grain of mustard seed, (yet) will We bring it, and sufficient are We to take account.
Here the Qur’an refers to the scales that will be used to measure a person’s good deeds against their bad deeds on the day of judgement. If the scales are heavy with good deeds, the Muslim can go to paradise. If the scales are light, the Muslim will spend eternity in Hellfire. Here the mustard seed is used as an illustration of how exacting the measurement will be. If your bad deeds outweigh your good deeds by just a smidgeon, your fate is sealed. The Qur’an has other such verses that reiterate the same concept. For example, consider chapter 99, verses 6-8
[99.6-8] On that day men shall come forth in sundry bodies that they may be shown their works. So he who has done an atom’s weight of good shall see it. And he who has done an atom’s weight of evil shall see it.
Ultimately, Allah’s decision on the Muslim’s salvation is measured by good deeds versus bad deeds, and everything, no matter how microscopic, will be counted.
So in both Christianity and Islam, the mustard seed is used to signify how tiny something must be in order to be counted. Yet what it refers to isn’t just different, but completely antithetical. In Islam, the smallest of acts can be counted against your account. In Christianity, the smallest amount of faith in Jesus provides access to eternal life with Him. Both religions use the tiny mustard seed to make an example, yet the same object represents two totally different conceptions of salvation.