Question:
If two very strong Christians get married, but one is much stronger than the other; is that bad?

Answer:
“Iron sharpeneth iron; so a man sharpeneth the countenance of his friend” (Proverbs 27:17).

If you both have the desire to please the Lord you will be studying and praying together, and thus growing together in the Lord. But each person must be willing to have their weaknesses pointed out, in order to become more like Christ.