I put these points at the top of my sermon-prep template to remind myself every week:

• Show that main point of passage relates to Jesus and his saving work
• (1 Cor 1:18) A truly gospel-centred message will not be acceptable in a synagogue or mosque
• Did I proclaim the gospel as the headline news of the sermon, rather than as a “by the way…”?
• Unbelievers are called to repent, believe, and be saved
• Believers are encouraged to abandon their old self, renew their minds, put on the new self in Christ
• Preach simple sermons, so that God’s people can see Christ more clearly and love him more dearly