Westminster Larger Catechism

One who doubteth of his being in Christ, or of his due preparation to the sacrament of the Lord's supper, may have true interest in Christ, though he be not yet assured thereof;¹¹⁰² and in God's account hath it, if he be duly affected with the apprehension of the want of it,¹¹⁰³ and unfeignedly desires to be found in Christ,¹¹⁰⁴ and to depart from iniquity;¹¹⁰⁵ in which case (because promises are made, and this sacrament is appointed, for the relief even of weak and doubting Christians¹¹⁰⁶) he is to bewail his unbelief,¹¹⁰⁷ and labor to have his doubts resolved;¹¹⁰⁸ and, so doing, he may and ought to come to the Lord's supper, that he may be further strengthened.¹¹⁰⁹